PNG decoder conformance

This project contains a suite of crafted PNG files built to test PNG readers against the specification and against each other. I hope it can help you answer the question, "Which PNG library should I use?", and "How reliable is my software, anyway?".

The results likely contain errors, or decisions which can be argued with. Regardless, I did take quite a bit of care to make this meaningful, more than you'll see from the typical vibeslop project.

The initial decisions here came from several rounds of Matt Pocock's grill-me Skill and at least four separate essays I wrote while trying to keep Claude Opus 5.5 on track, alongside several rounds of adversarial checking from GPT-6 Astra and from Claude Fable 5.1. I had to "push back" quite a lot to get past the AI's boneheaded decisions.

Further work mostly came from discussing things with Claude Fable 5.1, over several days and many sessions, and having him orchestrate Claude Opus 5.5 subagents for most implementation work.

My conclusion: Parsing PNGs is a Minefield. A modern JSON comparison is coming Soon™, don't worry :)

The rest of this document was written by AIs. Everything before this point was written by me, a flesh-and-blood human.

Every decoder below was run over the same 699 small PNG files from difftest-png, each one built to test one rule of the PNG specification or one behavior on which some decoder deviates. Run 2026-10-30T05:09:40+00:00 on Linux x86_64.

Each result is rated under each lens: pass, should (the specification says a decoder should do otherwise, e.g. recover a recoverable fault instead of rejecting the image) or must (a requirement is broken: wrong pixels, an invalid file accepted, a valid file rejected, a result that is not an image, a crash, a hang, a memory error). Warnings never count against a decoder. Running out of memory counts like a crash: a file should be rejected with an error, and a decoder that instead exhausts its host hands every program that opens untrusted images a denial of service. Pixels are compared as 16-bit RGBA with no color management; color under fully transparent pixels and the 8-bit reduction of 16-bit images are recorded as properties, not failures. Validators (pngcheck) are judged on a different question: whether each file conforms to the specification. Some files a decoder must still display do not conform, for example one with a chunk name the specification reserves.

Two editions of the specification matter: the second (ISO/IEC 15948:2003; PNG 1.0 and 1.1 count as the second) and the third (W3C, 2025). A lens is an edition's text plus the extensions: the W3C registered extensions, Apple's iDOT, and under the second edition the chunks the third edition added (APNG, cICP, mDCV, cLLI, eXIf). Every result is rated through both lenses separately; each table has a checkbox per edition, and shows the ticked ones. There is no single verdict: following one edition rather than the other is not a defect. The two ratings differ only where the texts contradict each other, which they do in one place: a palette index past the end of PLTE is an error in the second edition and renders opaque black in the third.

Not tested: animation frames after the default image, color management (gAMA, cHRM, iCCP, sRGB, cICP, sBIT), encoders, performance. Passing every test means the suite is incomplete, not that the decoder is perfect.

Legend

cell	counts as	meaning
✓	pass	decoded to the pixels of one of the reference's interpretations; a validator: accepted a conforming file
✓^t	pass	one of several tRNS chunks used: an arguable choice; the letter also marks an A
✓^c	pass	a chunk with a bad CRC used as stored: an arguable choice; the letter also marks an A
✓^p	pass	one of several PLTE chunks used: an arguable choice; the letter also marks an A
✓^k	pass	an unknown critical chunk ignored: an arguable choice; the letter also marks an A
A	pass	decoded a file that has no reference pixels, which the lens allows to be rejected
A	must-violation	decoded a file the lens says to reject; a validator: accepted a file that does not conform
R	pass	rejected a file the lens allows to be rejected; a validator: rejected a file that does not conform
R	should-violation	rejected a file a decoder should recover and display
R	must-violation	rejected a valid file; a validator: rejected a conforming file
≠	must-violation	decoded to pixels no interpretation has
☠	must-violation	crashed
⧗	must-violation	timed out
∞	must-violation	ran out of memory
M	must-violation	memory error under valgrind memcheck, whatever the outcome
!	must-violation	returned without error, but not an image: wrong size, missing rows or non-numeric samples
-	not scored	the wrapper itself failed; listed under problems

Implementations

implementation	version	lineage	diagnostics
reference-2	refpng 2.0 (PNG reference decoder: every interpretation, own inflate)	this project	WARN/ERR protocol
reference-3	refpng 2.0 (PNG reference decoder: every interpretation, own inflate)	this project	WARN/ERR protocol
pngcheck	PNGcheck, version 4.0.0	pngcheck	stdout validation report and exit status
pngcheck-head	bd33ad6 2025-12-15	pngcheck	stdout validation report and exit status
chunky_png chunky_png-head	chunky_png 1.4.0 (ruby 3.4.10) 7a1faf6 2021-06-06	chunky_png	errors only; no recoverable-warning channel
fast-png fast-png-head	fast-png 8.0.0 (node v26.11.1) 31b93cf 2026-04-12	fast-png	errors only; no recoverable-warning channel
ffmpeg	ffmpeg version n9.0.2	ffmpeg	stderr warnings and errors
ffmpeg-head	179d083 2026-10-22	ffmpeg	stderr warnings and errors
go-png go-png-head	go image/png go1.27.3-X:nodwarf5 5391dd5 2026-10-22	go	errors only; no recoverable-warning channel
graphicsmagick	GraphicsMagick 1.3.48 2026-07-23 Q16	libpng	stderr warnings and errors
graphicsmagick-head	hg 18216:0ca2165aa07c 2026-10-21	libpng	stderr warnings and errors
imagemagick	ImageMagick 7.1.2-32 Q16-HDRI x86_64 68f8d115a:20260926	libpng	stderr warnings and errors
imagemagick-head	a0ac982 2026-10-22	libpng	stderr warnings and errors
imagesharp imagesharp-head	ImageSharp 3.1.12 (.NET 9.0.17) d1367d4 2026-04-07	imagesharp	errors only; no recoverable-warning channel
java-imageio	Java ImageIO (Arch Linux 27)	java	warning listener and exception causes
libpng libpng16-head	libpng 1.6.59 (built against 1.6.59) 8c2a5fb 2026-10-21	libpng	warning and error callbacks
libpng18-head	682e5fe 2026-10-21	libpng	warning and error callbacks
libspng libspng-head	libspng 0.7.4 46c81dc 2026-08-31	libspng	errors only; no recoverable-warning channel
lodepng lodepng-head	lodepng 20261006 e584a84 2026-10-06	lodepng	errors only; no recoverable-warning channel
opencv	OpenCV 5.0.0 (PNG: /usr/local/lib/libpng.so (ver 1.6.58))	libpng	native stderr and errors
opencv-head	ce58bb1 2026-10-22	libpng	native stderr and errors
pillow	Pillow 13.0.0	pillow	Python warnings and exceptions
pillow-head	d4b99a3 2026-10-23	pillow	Python warnings and exceptions
pngjs	pngjs 7.0.0 (node v26.11.1)	pngjs	errors only; no recoverable-warning channel
pngjs-head	c565210 2023-05-06	pngjs	errors only; no recoverable-warning channel
pngtopam	Netpbm 10.86.51	libpng	stderr warnings and errors
pngtopam-head	svn advanced r5409, last changed r5388 2026-10-08	libpng	stderr warnings and errors
pypng	pypng 0.20220715.0	pypng	Python warnings and exceptions
pypng-head	f6899c4 2025-10-29	pypng	Python warnings and exceptions
rust-png	png 0.18.1	image-rs	errors only; no recoverable-warning channel
rust-png-head	b2f10c6 2026-09-23	image-rs	errors only; no recoverable-warning channel
stb_image stb_image-head	stb_image v2.30 a7d4c21 2026-10-19	stb	errors only; no recoverable-warning channel
upng	upng-js 2.1.0 (node v26.11.1)	upng	errors only; no recoverable-warning channel
upng-head	88f504b 2023-07-22	upng	errors only; no recoverable-warning channel
wuffs wuffs-head	wuffs 0.4.0-alpha.12+4048.20261020 4be865d 2026-10-21	wuffs	errors only; no recoverable-warning channel
zune-png	zune-png 0.5.2	zune	errors only; upstream warning macros are no-ops
zune-png-head	33007f6 2026-10-22	zune	errors only; upstream warning macros are no-ops

Violations

2nd edition 3rd edition

		reference		validators		decoders
		reference-2	reference-3	pngcheck	pngcheck-head	chunky_png · chunky_png-head	fast-png · fast-png-head	ffmpeg	ffmpeg-head	go-png · go-png-head	graphicsmagick	graphicsmagick-head	imagemagick	imagemagick-head	imagesharp · imagesharp-head	java-imageio	libpng · libpng16-head	libpng18-head	libspng · libspng-head	lodepng · lodepng-head	opencv	opencv-head	pillow	pillow-head	pngjs	pngjs-head	pngtopam	pngtopam-head	pypng	pypng-head	rust-png	rust-png-head	stb_image · stb_image-head	upng	upng-head	wuffs · wuffs-head	zune-png	zune-png-head
2nd edition	valid file rejected	0	0	3	3	2	52	5	5	2	4	4	4	4	26	2	4	4	3	2	4	4	2	2	2	2	4	4	2	2	2	2	0	3	1	5	2	2
	invalid file accepted	0	5	53	54	14	18	25	25	10	1	1	1	1	20	15	7	7	7	9	6	6	18	18	13	13	7	7	8	8	8	8	10	37	47	9	17	17
	wrong pixels	0	0	0	0	14	36	17	17	5	14	14	7	7	99	17	0	0	6	9	27	27	24	24	11	11	20	9	14	8	6	6	4	111	141	4	8	4
	crash, hang, out of memory or memory error	0	0	0	0	2	3	0	0	2	0	0	0	1	0	0	0	0	0	3	0	0	0	0	0	0	0	13	2	2	0	0	5	6	7	1	0	0
	no usable image returned	0	0	0	0	7	17	0	0	0	0	0	0	0	0	0	0	0	0	0	0	0	0	0	0	0	0	0	7	7	0	0	0	9	4	0	0	0
	recoverable file rejected	0	0	0	0	16	22	16	16	15	1	1	1	1	13	4	1	5	3	65	9	9	25	25	13	13	1	1	23	20	10	11	11	14	22	19	21	25
	silent	0	0	53	54	172	179	151	150	163	90	90	74	74	194	192	66	54	188	112	59	63	171	171	178	175	61	61	152	155	179	178	188	205	214	170	179	179
	strict			5
3rd edition	valid file rejected	0	0	3	3	2	52	5	5	2	4	4	4	4	26	2	4	4	3	2	4	4	2	2	2	2	4	4	2	2	2	2	0	3	1	5	2	2
	invalid file accepted	0	0	53	54	14	18	20	20	5	1	1	1	1	15	10	2	2	2	4	1	1	13	13	13	13	2	2	8	8	3	3	10	32	42	4	12	12
	wrong pixels	0	0	0	0	14	36	17	17	5	14	14	7	7	104	17	0	0	6	9	27	27	24	24	11	11	20	9	14	8	6	6	4	111	141	4	8	4
	crash, hang, out of memory or memory error	0	0	0	0	2	3	0	0	2	0	0	0	1	0	0	0	0	0	3	0	0	0	0	0	0	0	13	2	2	0	0	5	6	7	1	0	0
	no usable image returned	0	0	0	0	7	17	0	0	0	0	0	0	0	0	0	0	0	0	0	0	0	0	0	0	0	0	0	7	7	0	0	0	9	4	0	0	0
	recoverable file rejected	5	0	0	0	16	27	16	16	15	6	6	6	6	13	4	1	5	3	65	9	9	25	25	18	18	1	1	28	25	10	11	11	14	22	19	21	25
	silent	0	0	53	54	172	179	151	150	163	90	90	74	74	194	192	66	54	188	112	59	63	171	171	178	175	61	61	152	155	179	178	188	205	214	170	179	179
	strict			5

The first five rows are must-violations and the sixth should-violations. silent: the column accepted a file that does not conform and said nothing about it; a count, not a violation. strict: a validator rejected a file that conforms, over a name a strict reading of the naming rules may flag (iDOT's unregistered public name); recorded, not a violation.

chunky_png, pillow and upng return at most 8 bits per sample. All of them keep the high byte of a 16-bit sample and drop the low byte.

Every decoder preserves the color under fully transparent pixels, except chunky_png, pngjs and wuffs: they zero it under a tRNS color key.

By family

2nd edition 3rd edition

		reference		validators		decoders
family		reference-2	reference-3	pngcheck	pngcheck-head	chunky_png · chunky_png-head	fast-png · fast-png-head	ffmpeg	ffmpeg-head	go-png · go-png-head	graphicsmagick	graphicsmagick-head	imagemagick	imagemagick-head	imagesharp · imagesharp-head	java-imageio	libpng · libpng16-head	libpng18-head	libspng · libspng-head	lodepng · lodepng-head	opencv	opencv-head	pillow	pillow-head	pngjs	pngjs-head	pngtopam	pngtopam-head	pypng	pypng-head	rust-png	rust-png-head	stb_image · stb_image-head	upng	upng-head	wuffs · wuffs-head	zune-png	zune-png-head
2nd edition	Filters	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	18/105	✓	✓	✓	✓
	Interlacing	✓	✓	✓	✓	✓	60/208	✓	✓	✓	✓	✓	✓	✓	106/208	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	62/208	113/208	✓	✓	✓
	Bit packing	✓	✓	✓	✓	✓	1/7	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	4/7	1/7	✓	✓	✓
	IDAT and zlib	✓	✓	11/30	11/30	3/30	4/30	2/30	2/30	✓	1/30	1/30	1/30	1/30	11/30	1/30	1/30	1/30	1/30	4/30	1/30	1/30	1/30	1/30	8/30	8/30	1/30	1/30	5/30	5/30	2/30	2/30	5/30	2/30	7/30	5/30	4/30	6/30
	DEFLATE	✓	✓	3/22	3/22	2/22	1/22	2/22	2/22	2/22	2/22	2/22	2/22	2/22	2/22	2/22	2/22	2/22	2/22	✓	2/22	2/22	2/22	2/22	2/22	2/22	2/22	2/22	2/22	2/22	2/22	2/22	✓	2/22	4/22	4/22	✓	✓
	IHDR	✓	✓	1/24	1/24	7/24	10/24	6/24	6/24	2/24	✓	✓	✓	✓	4/24	2/24	1/24	1/24	✓	1/24	✓	✓	5/24	5/24	7/24	7/24	1/24	1/24	6/24	6/24	✓	✓	4/24	24/24	24/24	✓	5/24	5/24
	PLTE	✓	5/18	5/18	5/18	8/18	3/18	9/18	9/18	8/18	1/18	1/18	1/18	1/18	7/18	8/18	6/18	6/18	7/18	8/18	6/18	6/18	8/18	8/18	2/18	2/18	6/18	6/18	2/18	2/18	6/18	7/18	6/18	9/18	9/18	6/18	8/18	7/18
	tRNS	✓	✓	1/56	1/56	16/56	47/56	15/56	15/56	16/56	13/56	13/56	7/56	7/56	13/56	20/56	✓	✓	7/56	17/56	26/56	26/56	26/56	26/56	15/56	15/56	17/56	19/56	15/56	15/56	6/56	6/56	14/56	26/56	23/56	7/56	15/56	8/56
	Chunks	✓	✓	✓	✓	5/35	5/35	8/35	8/35	4/35	2/35	2/35	2/35	2/35	3/35	4/35	2/35	2/35	2/35	2/35	2/35	2/35	4/35	4/35	3/35	3/35	2/35	2/35	3/35	3/35	1/35	1/35	✓	9/35	9/35	1/35	1/35	1/35
	Ancillary chunks	✓	✓	29/144	29/144	13/144	15/144	15/144	15/144	✓	1/144	1/144	✓	✓	8/144	1/144	✓	2/144	✓	54/144	9/144	9/144	19/144	19/144	2/144	2/144	3/144	3/144	20/144	11/144	7/144	7/144	✓	10/144	20/144	7/144	11/144	18/144
	iDOT	✓	✓	✓	1/8	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓
	APNG	✓	✓	3/36	3/36	✓	✓	6/36	6/36	✓	✓	✓	✓	✓	4/36	✓	✓	2/36	✓	✓	✓	✓	4/36	4/36	✓	✓	✓	✓	✓	✓	2/36	2/36	✓	12/36	9/36	7/36	2/36	1/36
	Dimensions	✓	✓	3/5	3/5	1/5	2/5	✓	✓	2/5	✓	✓	✓	1/5	✓	✓	✓	✓	✓	2/5	✓	✓	✓	✓	✓	✓	✓	✓	3/5	3/5	✓	✓	✓	2/5	2/5	1/5	2/5	2/5
	CgBI	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	1/1	✓	1/1	✓	✓	✓
3rd edition	Filters	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	18/105	✓	✓	✓	✓
	Interlacing	✓	✓	✓	✓	✓	60/208	✓	✓	✓	✓	✓	✓	✓	106/208	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	62/208	113/208	✓	✓	✓
	Bit packing	✓	✓	✓	✓	✓	1/7	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	4/7	1/7	✓	✓	✓
	IDAT and zlib	✓	✓	11/30	11/30	3/30	4/30	2/30	2/30	✓	1/30	1/30	1/30	1/30	11/30	1/30	1/30	1/30	1/30	4/30	1/30	1/30	1/30	1/30	8/30	8/30	1/30	1/30	5/30	5/30	2/30	2/30	5/30	2/30	7/30	5/30	4/30	6/30
	DEFLATE	✓	✓	3/22	3/22	2/22	1/22	2/22	2/22	2/22	2/22	2/22	2/22	2/22	2/22	2/22	2/22	2/22	2/22	✓	2/22	2/22	2/22	2/22	2/22	2/22	2/22	2/22	2/22	2/22	2/22	2/22	✓	2/22	4/22	4/22	✓	✓
	IHDR	✓	✓	1/24	1/24	7/24	10/24	6/24	6/24	2/24	✓	✓	✓	✓	4/24	2/24	1/24	1/24	✓	1/24	✓	✓	5/24	5/24	7/24	7/24	1/24	1/24	6/24	6/24	✓	✓	4/24	24/24	24/24	✓	5/24	5/24
	PLTE	5/18	✓	5/18	5/18	8/18	8/18	4/18	4/18	3/18	6/18	6/18	6/18	6/18	7/18	3/18	1/18	1/18	2/18	3/18	1/18	1/18	3/18	3/18	7/18	7/18	1/18	1/18	7/18	7/18	1/18	2/18	6/18	4/18	4/18	1/18	3/18	2/18
	tRNS	✓	✓	1/56	1/56	16/56	47/56	15/56	15/56	16/56	13/56	13/56	7/56	7/56	13/56	20/56	✓	✓	7/56	17/56	26/56	26/56	26/56	26/56	15/56	15/56	17/56	19/56	15/56	15/56	6/56	6/56	14/56	26/56	23/56	7/56	15/56	8/56
	Chunks	✓	✓	✓	✓	5/35	5/35	8/35	8/35	4/35	2/35	2/35	2/35	2/35	3/35	4/35	2/35	2/35	2/35	2/35	2/35	2/35	4/35	4/35	3/35	3/35	2/35	2/35	3/35	3/35	1/35	1/35	✓	9/35	9/35	1/35	1/35	1/35
	Ancillary chunks	✓	✓	29/144	29/144	13/144	15/144	15/144	15/144	✓	1/144	1/144	✓	✓	8/144	1/144	✓	2/144	✓	54/144	9/144	9/144	19/144	19/144	2/144	2/144	3/144	3/144	20/144	11/144	7/144	7/144	✓	10/144	20/144	7/144	11/144	18/144
	iDOT	✓	✓	✓	1/8	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓
	APNG	✓	✓	3/36	3/36	✓	✓	6/36	6/36	✓	✓	✓	✓	✓	4/36	✓	✓	2/36	✓	✓	✓	✓	4/36	4/36	✓	✓	✓	✓	✓	✓	2/36	2/36	✓	12/36	9/36	7/36	2/36	1/36
	Dimensions	✓	✓	3/5	3/5	1/5	2/5	✓	✓	2/5	✓	✓	✓	1/5	✓	✓	✓	✓	✓	2/5	✓	✓	✓	✓	✓	✓	✓	✓	3/5	3/5	✓	✓	✓	2/5	2/5	1/5	2/5	2/5
	CgBI	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	1/1	✓	1/1	✓	✓	✓

Results

2nd edition 3rd edition	reference	validators	decoders
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y_filter-none-g1png IHDRIDATIEND every scanline uses None: the plain g1 picture. expected: display, conforms spec: §9.2 expected43 match 94 of 195 pixels differ1: upng	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	≠	✓	✓	✓	✓
y_filter-sub-g1png IHDRIDATIEND every scanline uses Sub; the subtraction wraps in 7 bytes. expected: display, conforms spec: §9.2 expected43 match 94 of 195 pixels differ1: upng	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	≠	✓	✓	✓	✓
y_filter-up-g1png IHDRIDATIEND every scanline uses Up; the subtraction wraps in 3 bytes. expected: display, conforms spec: §9.2 expected43 match 94 of 195 pixels differ1: upng	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	≠	✓	✓	✓	✓
y_filter-average-g1png IHDRIDATIEND every scanline uses Average; a + b is odd in 13 bytes and exceeds 255 in 1. expected: display, conforms spec: §9.2, §9.3 expected43 match 94 of 195 pixels differ1: upng	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	≠	✓	✓	✓	✓
y_filter-paeth-g1png IHDRIDATIEND every scanline uses Paeth; the predictor is a in 10 bytes, b in 19, c in 1, and 0 ties go by comparison order. expected: display, conforms spec: §9.2, §9.4 expected43 match 94 of 195 pixels differ1: upng	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	≠	✓	✓	✓	✓
y_filter-mix-g1png IHDRIDATIEND each filter type on three scanlines, in a seeded random order. expected: display, conforms spec: §9.2, §9.3, §9.4 expected43 match 94 of 195 pixels differ1: upng	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	≠	✓	✓	✓	✓
y_tiny-1x1-g1png IHDRIDATIEND the picture's top-left pixel alone, Paeth filtered. Table 12 in §11.2.1 lists this combination, and decoders must support every one. expected: display, conforms spec: Table 12, §15.3.3 expected44 match	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓
y_filter-none-g2png IHDRIDATIEND every scanline uses None: the plain g2 picture. expected: display, conforms spec: §9.2 expected43 match 118 of 195 pixels differ1: upng	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	≠	✓	✓	✓	✓
y_filter-sub-g2png IHDRIDATIEND every scanline uses Sub; the subtraction wraps in 19 bytes. expected: display, conforms spec: §9.2 expected43 match 118 of 195 pixels differ1: upng	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	≠	✓	✓	✓	✓
y_filter-up-g2png IHDRIDATIEND every scanline uses Up; the subtraction wraps in 7 bytes. expected: display, conforms spec: §9.2 expected43 match 118 of 195 pixels differ1: upng	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	≠	✓	✓	✓	✓
y_filter-average-g2png IHDRIDATIEND every scanline uses Average; a + b is odd in 27 bytes and exceeds 255 in 20. expected: display, conforms spec: §9.2, §9.3 expected43 match 118 of 195 pixels differ1: upng	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	≠	✓	✓	✓	✓
y_filter-paeth-g2png IHDRIDATIEND every scanline uses Paeth; the predictor is a in 19 bytes, b in 40, c in 1, and 0 ties go by comparison order. expected: display, conforms spec: §9.2, §9.4 expected43 match 118 of 195 pixels differ1: upng	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	≠	✓	✓	✓	✓
y_filter-mix-g2png IHDRIDATIEND each filter type on three scanlines, in a seeded random order. expected: display, conforms spec: §9.2, §9.3, §9.4 expected43 match 118 of 195 pixels differ1: upng	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	≠	✓	✓	✓	✓
y_tiny-1x1-g2png IHDRIDATIEND the picture's top-left pixel alone, Paeth filtered. Table 12 in §11.2.1 lists this combination, and decoders must support every one. expected: display, conforms spec: Table 12, §15.3.3 expected44 match	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓
y_filter-none-g4png IHDRIDATIEND every scanline uses None: the plain g4 picture. expected: display, conforms spec: §9.2 expected43 match 122 of 195 pixels differ1: upng	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	≠	✓	✓	✓	✓
y_filter-sub-g4png IHDRIDATIEND every scanline uses Sub; the subtraction wraps in 21 bytes. expected: display, conforms spec: §9.2 expected43 match 122 of 195 pixels differ1: upng	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	≠	✓	✓	✓	✓
y_filter-up-g4png IHDRIDATIEND every scanline uses Up; the subtraction wraps in 15 bytes. expected: display, conforms spec: §9.2 expected43 match 122 of 195 pixels differ1: upng	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	≠	✓	✓	✓	✓
y_filter-average-g4png IHDRIDATIEND every scanline uses Average; a + b is odd in 66 bytes and exceeds 255 in 35. expected: display, conforms spec: §9.2, §9.3 expected43 match 122 of 195 pixels differ1: upng	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	≠	✓	✓	✓	✓
y_filter-paeth-g4png IHDRIDATIEND every scanline uses Paeth; the predictor is a in 46 bytes, b in 57, c in 2, and 0 ties go by comparison order. expected: display, conforms spec: §9.2, §9.4 expected43 match 122 of 195 pixels differ1: upng	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	≠	✓	✓	✓	✓
y_filter-mix-g4png IHDRIDATIEND each filter type on three scanlines, in a seeded random order. expected: display, conforms spec: §9.2, §9.3, §9.4 expected43 match 122 of 195 pixels differ1: upng	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	≠	✓	✓	✓	✓
y_tiny-1x1-g4png IHDRIDATIEND the picture's top-left pixel alone, Paeth filtered. Table 12 in §11.2.1 lists this combination, and decoders must support every one. expected: display, conforms spec: Table 12, §15.3.3 expected44 match	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓
y_filter-none-g8png IHDRIDATIEND every scanline uses None: the plain g8 picture. expected: display, conforms spec: §9.2 expected44 match	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓
y_filter-sub-g8png IHDRIDATIEND every scanline uses Sub; the subtraction wraps in 16 bytes. expected: display, conforms spec: §9.2 expected44 match	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓
y_filter-up-g8png IHDRIDATIEND every scanline uses Up; the subtraction wraps in 24 bytes. expected: display, conforms spec: §9.2 expected44 match	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓
y_filter-average-g8png IHDRIDATIEND every scanline uses Average; a + b is odd in 90 bytes and exceeds 255 in 79. expected: display, conforms spec: §9.2, §9.3 expected44 match	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓
y_filter-paeth-g8png IHDRIDATIEND every scanline uses Paeth; the predictor is a in 116 bytes, b in 73, c in 6, and 0 ties go by comparison order. expected: display, conforms spec: §9.2, §9.4 expected44 match	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓
y_filter-mix-g8png IHDRIDATIEND each filter type on three scanlines, in a seeded random order. expected: display, conforms spec: §9.2, §9.3, §9.4 expected44 match	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓
y_tiny-1x1-g8png IHDRIDATIEND the picture's top-left pixel alone, Paeth filtered. Table 12 in §11.2.1 lists this combination, and decoders must support every one. expected: display, conforms spec: Table 12, §15.3.3 expected44 match	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓
y_filter-none-g16png IHDRIDATIEND every scanline uses None: the plain g16 picture. expected: display, conforms spec: §9.2 expected40 match matches the reference; 16→8 high byte4: upng, chunky_png, upng-head, chunky_png-head	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓
y_filter-sub-g16png IHDRIDATIEND every scanline uses Sub; the subtraction wraps in 37 bytes. expected: display, conforms spec: §9.2 expected40 match matches the reference; 16→8 high byte4: upng, chunky_png, upng-head, chunky_png-head	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓
y_filter-up-g16png IHDRIDATIEND every scanline uses Up; the subtraction wraps in 120 bytes. expected: display, conforms spec: §9.2 expected40 match matches the reference; 16→8 high byte4: upng, chunky_png, upng-head, chunky_png-head	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓
y_filter-average-g16png IHDRIDATIEND every scanline uses Average; a + b is odd in 232 bytes and exceeds 255 in 163. expected: display, conforms spec: §9.2, §9.3 expected40 match matches the reference; 16→8 high byte4: upng, chunky_png, upng-head, chunky_png-head	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓
y_filter-paeth-g16png IHDRIDATIEND every scanline uses Paeth; the predictor is a in 236 bytes, b in 145, c in 9, and 1 ties go by comparison order. expected: display, conforms spec: §9.2, §9.4 expected40 match matches the reference; 16→8 high byte4: upng, chunky_png, upng-head, chunky_png-head	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓
y_filter-mix-g16png IHDRIDATIEND each filter type on three scanlines, in a seeded random order. expected: display, conforms spec: §9.2, §9.3, §9.4 expected40 match matches the reference; 16→8 high byte4: upng, chunky_png, upng-head, chunky_png-head	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓
y_tiny-1x1-g16png IHDRIDATIEND the picture's top-left pixel alone, Paeth filtered. Table 12 in §11.2.1 lists this combination, and decoders must support every one. expected: display, conforms spec: Table 12, §15.3.3 expected40 match matches the reference; 16→8 high byte4: upng, chunky_png, upng-head, chunky_png-head	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓
y_filter-none-rgb8png IHDRIDATIEND every scanline uses None: the plain rgb8 picture. expected: display, conforms spec: §9.2 expected44 match	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓
y_filter-sub-rgb8png IHDRIDATIEND every scanline uses Sub; the subtraction wraps in 44 bytes. expected: display, conforms spec: §9.2 expected44 match	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓
y_filter-up-rgb8png IHDRIDATIEND every scanline uses Up; the subtraction wraps in 156 bytes. expected: display, conforms spec: §9.2 expected44 match	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓
y_filter-average-rgb8png IHDRIDATIEND every scanline uses Average; a + b is odd in 287 bytes and exceeds 255 in 153. expected: display, conforms spec: §9.2, §9.3 expected44 match	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓
y_filter-paeth-rgb8png IHDRIDATIEND every scanline uses Paeth; the predictor is a in 356 bytes, b in 217, c in 12, and 2 ties go by comparison order. expected: display, conforms spec: §9.2, §9.4 expected44 match	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓
y_filter-mix-rgb8png IHDRIDATIEND each filter type on three scanlines, in a seeded random order. expected: display, conforms spec: §9.2, §9.3, §9.4 expected44 match	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓
y_tiny-1x1-rgb8png IHDRIDATIEND the picture's top-left pixel alone, Paeth filtered. Table 12 in §11.2.1 lists this combination, and decoders must support every one. expected: display, conforms spec: Table 12, §15.3.3 expected44 match	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓
y_filter-none-rgb16png IHDRIDATIEND every scanline uses None: the plain rgb16 picture. expected: display, conforms spec: §9.2 expected38 match matches the reference; 16→8 high byte6: upng, pillow, chunky_png, upng-head, pillow-head, chunky_png-head	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓
y_filter-sub-rgb16png IHDRIDATIEND every scanline uses Sub; the subtraction wraps in 165 bytes. expected: display, conforms spec: §9.2 expected38 match matches the reference; 16→8 high byte6: upng, pillow, chunky_png, upng-head, pillow-head, chunky_png-head	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓
y_filter-up-rgb16png IHDRIDATIEND every scanline uses Up; the subtraction wraps in 322 bytes. expected: display, conforms spec: §9.2 expected38 match matches the reference; 16→8 high byte6: upng, pillow, chunky_png, upng-head, pillow-head, chunky_png-head	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓
y_filter-average-rgb16png IHDRIDATIEND every scanline uses Average; a + b is odd in 609 bytes and exceeds 255 in 392. expected: display, conforms spec: §9.2, §9.3 expected38 match matches the reference; 16→8 high byte6: upng, pillow, chunky_png, upng-head, pillow-head, chunky_png-head	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓
y_filter-paeth-rgb16png IHDRIDATIEND every scanline uses Paeth; the predictor is a in 722 bytes, b in 428, c in 20, and 6 ties go by comparison order. expected: display, conforms spec: §9.2, §9.4 expected38 match matches the reference; 16→8 high byte6: upng, pillow, chunky_png, upng-head, pillow-head, chunky_png-head	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓
y_filter-mix-rgb16png IHDRIDATIEND each filter type on three scanlines, in a seeded random order. expected: display, conforms spec: §9.2, §9.3, §9.4 expected38 match matches the reference; 16→8 high byte6: upng, pillow, chunky_png, upng-head, pillow-head, chunky_png-head	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓
y_tiny-1x1-rgb16png IHDRIDATIEND the picture's top-left pixel alone, Paeth filtered. Table 12 in §11.2.1 lists this combination, and decoders must support every one. expected: display, conforms spec: Table 12, §15.3.3 expected38 match matches the reference; 16→8 high byte6: upng, pillow, chunky_png, upng-head, pillow-head, chunky_png-head	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓
y_filter-none-p1png IHDRPLTEIDATIEND every scanline uses None: the plain p1 picture. expected: display, conforms spec: §9.2 expected44 match	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓
y_filter-sub-p1png IHDRPLTEIDATIEND every scanline uses Sub; the subtraction wraps in 8 bytes. expected: display, conforms spec: §9.2 expected44 match	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓
y_filter-up-p1png IHDRPLTEIDATIEND every scanline uses Up; the subtraction wraps in 2 bytes. expected: display, conforms spec: §9.2 expected44 match	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓
y_filter-average-p1png IHDRPLTEIDATIEND every scanline uses Average; a + b is odd in 12 bytes and exceeds 255 in 5. expected: display, conforms spec: §9.2, §9.3 expected44 match	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓
y_filter-paeth-p1png IHDRPLTEIDATIEND every scanline uses Paeth; the predictor is a in 12 bytes, b in 17, c in 1, and 0 ties go by comparison order. expected: display, conforms spec: §9.2, §9.4 expected44 match	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓
y_filter-mix-p1png IHDRPLTEIDATIEND each filter type on three scanlines, in a seeded random order. expected: display, conforms spec: §9.2, §9.3, §9.4 expected44 match	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓
y_tiny-1x1-p1png IHDRPLTEIDATIEND the picture's top-left pixel alone, Paeth filtered. Table 12 in §11.2.1 lists this combination, and decoders must support every one. expected: display, conforms spec: Table 12, §15.3.3 expected44 match	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓
y_filter-none-p2png IHDRPLTEIDATIEND every scanline uses None: the plain p2 picture. expected: display, conforms spec: §9.2 expected44 match	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓
y_filter-sub-p2png IHDRPLTEIDATIEND every scanline uses Sub; the subtraction wraps in 10 bytes. expected: display, conforms spec: §9.2 expected44 match	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓
y_filter-up-p2png IHDRPLTEIDATIEND every scanline uses Up; the subtraction wraps in 13 bytes. expected: display, conforms spec: §9.2 expected44 match	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓
y_filter-average-p2png IHDRPLTEIDATIEND every scanline uses Average; a + b is odd in 31 bytes and exceeds 255 in 8. expected: display, conforms spec: §9.2, §9.3 expected44 match	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓
y_filter-paeth-p2png IHDRPLTEIDATIEND every scanline uses Paeth; the predictor is a in 35 bytes, b in 24, c in 1, and 0 ties go by comparison order. expected: display, conforms spec: §9.2, §9.4 expected44 match	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓
y_filter-mix-p2png IHDRPLTEIDATIEND each filter type on three scanlines, in a seeded random order. expected: display, conforms spec: §9.2, §9.3, §9.4 expected44 match	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓
y_tiny-1x1-p2png IHDRPLTEIDATIEND the picture's top-left pixel alone, Paeth filtered. Table 12 in §11.2.1 lists this combination, and decoders must support every one. expected: display, conforms spec: Table 12, §15.3.3 expected44 match	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓
y_filter-none-p4png IHDRPLTEIDATIEND every scanline uses None: the plain p4 picture. expected: display, conforms spec: §9.2 expected44 match	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓
y_filter-sub-p4png IHDRPLTEIDATIEND every scanline uses Sub; the subtraction wraps in 30 bytes. expected: display, conforms spec: §9.2 expected44 match	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓
y_filter-up-p4png IHDRPLTEIDATIEND every scanline uses Up; the subtraction wraps in 29 bytes. expected: display, conforms spec: §9.2 expected44 match	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓
y_filter-average-p4png IHDRPLTEIDATIEND every scanline uses Average; a + b is odd in 37 bytes and exceeds 255 in 52. expected: display, conforms spec: §9.2, §9.3 expected44 match	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓
y_filter-paeth-p4png IHDRPLTEIDATIEND every scanline uses Paeth; the predictor is a in 64 bytes, b in 41, c in 0, and 0 ties go by comparison order. expected: display, conforms spec: §9.2, §9.4 expected44 match	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓
y_filter-mix-p4png IHDRPLTEIDATIEND each filter type on three scanlines, in a seeded random order. expected: display, conforms spec: §9.2, §9.3, §9.4 expected44 match	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓
y_tiny-1x1-p4png IHDRPLTEIDATIEND the picture's top-left pixel alone, Paeth filtered. Table 12 in §11.2.1 lists this combination, and decoders must support every one. expected: display, conforms spec: Table 12, §15.3.3 expected44 match	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓
y_filter-none-p8png IHDRPLTEIDATIEND every scanline uses None: the plain p8 picture. expected: display, conforms spec: §9.2 expected44 match	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓
y_filter-sub-p8png IHDRPLTEIDATIEND every scanline uses Sub; the subtraction wraps in 16 bytes. expected: display, conforms spec: §9.2 expected44 match	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓
y_filter-up-p8png IHDRPLTEIDATIEND every scanline uses Up; the subtraction wraps in 3 bytes. expected: display, conforms spec: §9.2 expected44 match	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓
y_filter-average-p8png IHDRPLTEIDATIEND every scanline uses Average; a + b is odd in 126 bytes and exceeds 255 in 0. expected: display, conforms spec: §9.2, §9.3 expected44 match	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓
y_filter-paeth-p8png IHDRPLTEIDATIEND every scanline uses Paeth; the predictor is a in 130 bytes, b in 62, c in 3, and 3 ties go by comparison order. expected: display, conforms spec: §9.2, §9.4 expected44 match	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓
y_filter-mix-p8png IHDRPLTEIDATIEND each filter type on three scanlines, in a seeded random order. expected: display, conforms spec: §9.2, §9.3, §9.4 expected44 match	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓
y_tiny-1x1-p8png IHDRPLTEIDATIEND the picture's top-left pixel alone, Paeth filtered. Table 12 in §11.2.1 lists this combination, and decoders must support every one. expected: display, conforms spec: Table 12, §15.3.3 expected44 match	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓
y_filter-none-ga8png IHDRIDATIEND every scanline uses None: the plain ga8 picture. expected: display, conforms spec: §9.2 expected44 match	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓
y_filter-sub-ga8png IHDRIDATIEND every scanline uses Sub; the subtraction wraps in 76 bytes. expected: display, conforms spec: §9.2 expected44 match	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓
y_filter-up-ga8png IHDRIDATIEND every scanline uses Up; the subtraction wraps in 24 bytes. expected: display, conforms spec: §9.2 expected44 match	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓
y_filter-average-ga8png IHDRIDATIEND every scanline uses Average; a + b is odd in 128 bytes and exceeds 255 in 219. expected: display, conforms spec: §9.2, §9.3 expected44 match	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓
y_filter-paeth-ga8png IHDRIDATIEND every scanline uses Paeth; the predictor is a in 241 bytes, b in 143, c in 6, and 0 ties go by comparison order. expected: display, conforms spec: §9.2, §9.4 expected44 match	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓
y_filter-mix-ga8png IHDRIDATIEND each filter type on three scanlines, in a seeded random order. expected: display, conforms spec: §9.2, §9.3, §9.4 expected44 match	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓
y_tiny-1x1-ga8png IHDRIDATIEND the picture's top-left pixel alone, Paeth filtered. Table 12 in §11.2.1 lists this combination, and decoders must support every one. expected: display, conforms spec: Table 12, §15.3.3 expected44 match	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓
y_filter-none-ga16png IHDRIDATIEND every scanline uses None: the plain ga16 picture. expected: display, conforms spec: §9.2 expected38 match matches the reference; color under alpha 0 preserved; 16→8 high byte6: upng, pillow, chunky_png, upng-head, pillow-head, chunky_png-head	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓
y_filter-sub-ga16png IHDRIDATIEND every scanline uses Sub; the subtraction wraps in 112 bytes. expected: display, conforms spec: §9.2 expected38 match matches the reference; color under alpha 0 preserved; 16→8 high byte6: upng, pillow, chunky_png, upng-head, pillow-head, chunky_png-head	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓
y_filter-up-ga16png IHDRIDATIEND every scanline uses Up; the subtraction wraps in 120 bytes. expected: display, conforms spec: §9.2 expected38 match matches the reference; color under alpha 0 preserved; 16→8 high byte6: upng, pillow, chunky_png, upng-head, pillow-head, chunky_png-head	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓
y_filter-average-ga16png IHDRIDATIEND every scanline uses Average; a + b is odd in 308 bytes and exceeds 255 in 429. expected: display, conforms spec: §9.2, §9.3 expected38 match matches the reference; color under alpha 0 preserved; 16→8 high byte6: upng, pillow, chunky_png, upng-head, pillow-head, chunky_png-head	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓
y_filter-paeth-ga16png IHDRIDATIEND every scanline uses Paeth; the predictor is a in 528 bytes, b in 243, c in 9, and 1 ties go by comparison order. expected: display, conforms spec: §9.2, §9.4 expected38 match matches the reference; color under alpha 0 preserved; 16→8 high byte6: upng, pillow, chunky_png, upng-head, pillow-head, chunky_png-head	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓
y_filter-mix-ga16png IHDRIDATIEND each filter type on three scanlines, in a seeded random order. expected: display, conforms spec: §9.2, §9.3, §9.4 expected38 match matches the reference; color under alpha 0 preserved; 16→8 high byte6: upng, pillow, chunky_png, upng-head, pillow-head, chunky_png-head	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓
y_tiny-1x1-ga16png IHDRIDATIEND the picture's top-left pixel alone, Paeth filtered. Table 12 in §11.2.1 lists this combination, and decoders must support every one. expected: display, conforms spec: Table 12, §15.3.3 expected38 match matches the reference; 16→8 high byte6: upng, pillow, chunky_png, upng-head, pillow-head, chunky_png-head	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓
y_filter-none-rgba8png IHDRIDATIEND every scanline uses None: the plain rgba8 picture. expected: display, conforms spec: §9.2 expected44 match	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓
y_filter-sub-rgba8png IHDRIDATIEND every scanline uses Sub; the subtraction wraps in 104 bytes. expected: display, conforms spec: §9.2 expected44 match	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓
y_filter-up-rgba8png IHDRIDATIEND every scanline uses Up; the subtraction wraps in 156 bytes. expected: display, conforms spec: §9.2 expected44 match	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓
y_filter-average-rgba8png IHDRIDATIEND every scanline uses Average; a + b is odd in 325 bytes and exceeds 255 in 293. expected: display, conforms spec: §9.2, §9.3 expected44 match	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓
y_filter-paeth-rgba8png IHDRIDATIEND every scanline uses Paeth; the predictor is a in 481 bytes, b in 287, c in 12, and 2 ties go by comparison order. expected: display, conforms spec: §9.2, §9.4 expected44 match	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓
y_filter-mix-rgba8png IHDRIDATIEND each filter type on three scanlines, in a seeded random order. expected: display, conforms spec: §9.2, §9.3, §9.4 expected44 match	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓
y_tiny-1x1-rgba8png IHDRIDATIEND the picture's top-left pixel alone, Paeth filtered. Table 12 in §11.2.1 lists this combination, and decoders must support every one. expected: display, conforms spec: Table 12, §15.3.3 expected44 match	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓
y_filter-none-rgba16png IHDRIDATIEND every scanline uses None: the plain rgba16 picture. expected: display, conforms spec: §9.2 expected38 match matches the reference; color under alpha 0 preserved; 16→8 high byte6: upng, pillow, chunky_png, upng-head, pillow-head, chunky_png-head	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓
y_filter-sub-rgba16png IHDRIDATIEND every scanline uses Sub; the subtraction wraps in 240 bytes. expected: display, conforms spec: §9.2 expected38 match matches the reference; color under alpha 0 preserved; 16→8 high byte6: upng, pillow, chunky_png, upng-head, pillow-head, chunky_png-head	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓
y_filter-up-rgba16png IHDRIDATIEND every scanline uses Up; the subtraction wraps in 322 bytes. expected: display, conforms spec: §9.2 expected38 match matches the reference; color under alpha 0 preserved; 16→8 high byte6: upng, pillow, chunky_png, upng-head, pillow-head, chunky_png-head	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓
y_filter-average-rgba16png IHDRIDATIEND every scanline uses Average; a + b is odd in 685 bytes and exceeds 255 in 658. expected: display, conforms spec: §9.2, §9.3 expected38 match matches the reference; color under alpha 0 preserved; 16→8 high byte6: upng, pillow, chunky_png, upng-head, pillow-head, chunky_png-head	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓
y_filter-paeth-rgba16png IHDRIDATIEND every scanline uses Paeth; the predictor is a in 1014 bytes, b in 526, c in 20, and 6 ties go by comparison order. expected: display, conforms spec: §9.2, §9.4 expected38 match matches the reference; color under alpha 0 preserved; 16→8 high byte6: upng, pillow, chunky_png, upng-head, pillow-head, chunky_png-head	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓
y_filter-mix-rgba16png IHDRIDATIEND each filter type on three scanlines, in a seeded random order. expected: display, conforms spec: §9.2, §9.3, §9.4 expected38 match matches the reference; color under alpha 0 preserved; 16→8 high byte6: upng, pillow, chunky_png, upng-head, pillow-head, chunky_png-head	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓
y_tiny-1x1-rgba16png IHDRIDATIEND the picture's top-left pixel alone, Paeth filtered. Table 12 in §11.2.1 lists this combination, and decoders must support every one. expected: display, conforms spec: Table 12, §15.3.3 expected38 match matches the reference; 16→8 high byte6: upng, pillow, chunky_png, upng-head, pillow-head, chunky_png-head	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓
y_adam7-g1png IHDRIDATIEND 13x15, interlaced, random filter per scanline; no pass is empty. §8.1 says decoders are required to read interlaced images. expected: display, conforms spec: §13.10 expected40 match 89 of 195 pixels differ1: upng 12 of 195 pixels differ1: upng-head	✓	✓	✓	✓	✓	R	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	≠	≠	✓	✓	✓
y_adam7-1x1-g1png IHDRIDATIEND 1x1, interlaced, random filter per scanline; passes 2, 3, 4, 5, 6, 7 are empty. §8.1 says decoders are required to read interlaced images. §9.1 says an empty pass has no filter type bytes. §9.1 says an empty pass has no filter type bytes. expected: display, conforms spec: §13.10 expected44 match	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓
y_adam7-1x2-g1png IHDRIDATIEND 1x2, interlaced, random filter per scanline; passes 2, 3, 4, 5, 6 are empty. §8.1 says decoders are required to read interlaced images. §9.1 says an empty pass has no filter type bytes. §9.1 says an empty pass has no filter type bytes. expected: display, conforms spec: §13.10 expected44 match	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓
y_adam7-2x1-g1png IHDRIDATIEND 2x1, interlaced, random filter per scanline; passes 2, 3, 4, 5, 7 are empty. §8.1 says decoders are required to read interlaced images. §9.1 says an empty pass has no filter type bytes. §9.1 says an empty pass has no filter type bytes. expected: display, conforms spec: §13.10 expected42 match	✓	✓	✓	✓	✓	!	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓
y_adam7-2x2-g1png IHDRIDATIEND 2x2, interlaced, random filter per scanline; passes 2, 3, 4, 5 are empty. §8.1 says decoders are required to read interlaced images. §9.1 says an empty pass has no filter type bytes. §9.1 says an empty pass has no filter type bytes. expected: display, conforms spec: §13.10 expected42 match	✓	✓	✓	✓	✓	!	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓
y_adam7-3x3-g1png IHDRIDATIEND 3x3, interlaced, random filter per scanline; passes 2, 3 are empty. §8.1 says decoders are required to read interlaced images. §9.1 says an empty pass has no filter type bytes. §9.1 says an empty pass has no filter type bytes. expected: display, conforms spec: §13.10 expected42 match	✓	✓	✓	✓	✓	!	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓
y_adam7-4x4-g1png IHDRIDATIEND 4x4, interlaced, random filter per scanline; passes 2, 3 are empty. §8.1 says decoders are required to read interlaced images. §9.1 says an empty pass has no filter type bytes. §9.1 says an empty pass has no filter type bytes. expected: display, conforms spec: §13.10 expected38 match 6 of 16 pixels differ2: imagesharp, imagesharp-head 2 of 16 pixels differ1: upng-head 3 of 16 pixels differ1: upng	✓	✓	✓	✓	✓	R	✓	✓	✓	✓	✓	✓	✓	≠	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	≠	≠	✓	✓	✓
y_adam7-5x5-g1png IHDRIDATIEND 5x5, interlaced, random filter per scanline; no pass is empty. §8.1 says decoders are required to read interlaced images. expected: display, conforms spec: §13.10 expected40 match 5 of 25 pixels differ1: upng-head 7 of 25 pixels differ1: upng	✓	✓	✓	✓	✓	R	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	≠	≠	✓	✓	✓
y_adam7-1x9-g1png IHDRIDATIEND 1x9, interlaced, random filter per scanline; passes 2, 4, 6 are empty. §8.1 says decoders are required to read interlaced images. §9.1 says an empty pass has no filter type bytes. expected: display, conforms spec: §13.10 expected41 match 1 of 9 pixels differ3: imagesharp, upng, imagesharp-head	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	≠	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	≠	✓	✓	✓	✓
y_adam7-9x1-g1png IHDRIDATIEND 9x1, interlaced, random filter per scanline; passes 3, 5, 7 are empty. §8.1 says decoders are required to read interlaced images. §9.1 says an empty pass has no filter type bytes. expected: display, conforms spec: §13.10 expected42 match	✓	✓	✓	✓	✓	R	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓
y_adam7-2x7-g1png IHDRIDATIEND 2x7, interlaced, random filter per scanline; passes 2, 4 are empty. §8.1 says decoders are required to read interlaced images. §9.1 says an empty pass has no filter type bytes. expected: display, conforms spec: §13.10 expected42 match	✓	✓	✓	✓	✓	R	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓
y_adam7-7x2-g1png IHDRIDATIEND 7x2, interlaced, random filter per scanline; passes 3, 5 are empty. §8.1 says decoders are required to read interlaced images. §9.1 says an empty pass has no filter type bytes. expected: display, conforms spec: §13.10 expected42 match	✓	✓	✓	✓	✓	R	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓
y_adam7-8x9-g1png IHDRIDATIEND 8x9, interlaced, random filter per scanline; no pass is empty. §8.1 says decoders are required to read interlaced images. expected: display, conforms spec: §13.10 expected40 match 27 of 72 pixels differ1: upng 16 of 72 pixels differ1: upng-head	✓	✓	✓	✓	✓	R	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	≠	≠	✓	✓	✓
y_adam7-g2png IHDRIDATIEND 13x15, interlaced, random filter per scanline; no pass is empty. §8.1 says decoders are required to read interlaced images. expected: display, conforms spec: §13.10 expected40 match 118 of 195 pixels differ1: upng	✓	✓	✓	✓	✓	R	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	≠	R	✓	✓	✓
y_adam7-1x1-g2png IHDRIDATIEND 1x1, interlaced, random filter per scanline; passes 2, 3, 4, 5, 6, 7 are empty. §8.1 says decoders are required to read interlaced images. §9.1 says an empty pass has no filter type bytes. §9.1 says an empty pass has no filter type bytes. expected: display, conforms spec: §13.10 expected44 match	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓
y_adam7-1x2-g2png IHDRIDATIEND 1x2, interlaced, random filter per scanline; passes 2, 3, 4, 5, 6 are empty. §8.1 says decoders are required to read interlaced images. §9.1 says an empty pass has no filter type bytes. §9.1 says an empty pass has no filter type bytes. expected: display, conforms spec: §13.10 expected41 match 2 of 2 pixels differ2: imagesharp, imagesharp-head 1 of 2 pixels differ1: upng	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	≠	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	≠	✓	✓	✓	✓
y_adam7-2x1-g2png IHDRIDATIEND 2x1, interlaced, random filter per scanline; passes 2, 3, 4, 5, 7 are empty. §8.1 says decoders are required to read interlaced images. §9.1 says an empty pass has no filter type bytes. §9.1 says an empty pass has no filter type bytes. expected: display, conforms spec: §13.10 expected42 match	✓	✓	✓	✓	✓	!	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓
y_adam7-2x2-g2png IHDRIDATIEND 2x2, interlaced, random filter per scanline; passes 2, 3, 4, 5 are empty. §8.1 says decoders are required to read interlaced images. §9.1 says an empty pass has no filter type bytes. §9.1 says an empty pass has no filter type bytes. expected: display, conforms spec: §13.10 expected39 match 3 of 4 pixels differ2: imagesharp, imagesharp-head 2 of 4 pixels differ1: upng	✓	✓	✓	✓	✓	!	✓	✓	✓	✓	✓	✓	✓	≠	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	≠	✓	✓	✓	✓
y_adam7-3x3-g2png IHDRIDATIEND 3x3, interlaced, random filter per scanline; passes 2, 3 are empty. §8.1 says decoders are required to read interlaced images. §9.1 says an empty pass has no filter type bytes. §9.1 says an empty pass has no filter type bytes. expected: display, conforms spec: §13.10 expected38 match 7 of 9 pixels differ2: imagesharp, imagesharp-head 2 of 9 pixels differ1: upng 4 of 9 pixels differ1: upng-head	✓	✓	✓	✓	✓	R	✓	✓	✓	✓	✓	✓	✓	≠	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	≠	≠	✓	✓	✓
y_adam7-4x4-g2png IHDRIDATIEND 4x4, interlaced, random filter per scanline; passes 2, 3 are empty. §8.1 says decoders are required to read interlaced images. §9.1 says an empty pass has no filter type bytes. §9.1 says an empty pass has no filter type bytes. expected: display, conforms spec: §13.10 expected39 match 13 of 16 pixels differ2: imagesharp, imagesharp-head 4 of 16 pixels differ1: upng-head	✓	✓	✓	✓	✓	R	✓	✓	✓	✓	✓	✓	✓	≠	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	≠	✓	✓	✓
y_adam7-5x5-g2png IHDRIDATIEND 5x5, interlaced, random filter per scanline; no pass is empty. §8.1 says decoders are required to read interlaced images. expected: display, conforms spec: §13.10 expected40 match 6 of 25 pixels differ1: upng-head 14 of 25 pixels differ1: upng	✓	✓	✓	✓	✓	R	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	≠	≠	✓	✓	✓
y_adam7-1x9-g2png IHDRIDATIEND 1x9, interlaced, random filter per scanline; passes 2, 4, 6 are empty. §8.1 says decoders are required to read interlaced images. §9.1 says an empty pass has no filter type bytes. expected: display, conforms spec: §13.10 expected41 match 7 of 9 pixels differ2: imagesharp, imagesharp-head 7 of 9 pixels differ1: upng	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	≠	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	≠	✓	✓	✓	✓
y_adam7-9x1-g2png IHDRIDATIEND 9x1, interlaced, random filter per scanline; passes 3, 5, 7 are empty. §8.1 says decoders are required to read interlaced images. §9.1 says an empty pass has no filter type bytes. expected: display, conforms spec: §13.10 expected42 match	✓	✓	✓	✓	✓	R	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓
y_adam7-2x7-g2png IHDRIDATIEND 2x7, interlaced, random filter per scanline; passes 2, 4 are empty. §8.1 says decoders are required to read interlaced images. §9.1 says an empty pass has no filter type bytes. expected: display, conforms spec: §13.10 expected38 match 3 of 14 pixels differ2: imagesharp, imagesharp-head 2 of 14 pixels differ1: upng-head 6 of 14 pixels differ1: upng	✓	✓	✓	✓	✓	R	✓	✓	✓	✓	✓	✓	✓	≠	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	≠	≠	✓	✓	✓
y_adam7-7x2-g2png IHDRIDATIEND 7x2, interlaced, random filter per scanline; passes 3, 5 are empty. §8.1 says decoders are required to read interlaced images. §9.1 says an empty pass has no filter type bytes. expected: display, conforms spec: §13.10 expected40 match 1 of 14 pixels differ1: upng 7 of 14 pixels differ1: upng-head	✓	✓	✓	✓	✓	R	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	≠	≠	✓	✓	✓
y_adam7-8x9-g2png IHDRIDATIEND 8x9, interlaced, random filter per scanline; no pass is empty. §8.1 says decoders are required to read interlaced images. expected: display, conforms spec: §13.10 expected41 match 16 of 72 pixels differ1: upng-head	✓	✓	✓	✓	✓	R	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	≠	✓	✓	✓
y_adam7-g4png IHDRIDATIEND 13x15, interlaced, random filter per scanline; no pass is empty. §8.1 says decoders are required to read interlaced images. expected: display, conforms spec: §13.10 expected40 match 1 of 195 pixels differ1: upng-head 122 of 195 pixels differ1: upng	✓	✓	✓	✓	✓	R	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	≠	≠	✓	✓	✓
y_adam7-1x1-g4png IHDRIDATIEND 1x1, interlaced, random filter per scanline; passes 2, 3, 4, 5, 6, 7 are empty. §8.1 says decoders are required to read interlaced images. §9.1 says an empty pass has no filter type bytes. §9.1 says an empty pass has no filter type bytes. expected: display, conforms spec: §13.10 expected44 match	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓
y_adam7-1x2-g4png IHDRIDATIEND 1x2, interlaced, random filter per scanline; passes 2, 3, 4, 5, 6 are empty. §8.1 says decoders are required to read interlaced images. §9.1 says an empty pass has no filter type bytes. §9.1 says an empty pass has no filter type bytes. expected: display, conforms spec: §13.10 expected41 match 2 of 2 pixels differ2: imagesharp, imagesharp-head 1 of 2 pixels differ1: upng	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	≠	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	≠	✓	✓	✓	✓
y_adam7-2x1-g4png IHDRIDATIEND 2x1, interlaced, random filter per scanline; passes 2, 3, 4, 5, 7 are empty. §8.1 says decoders are required to read interlaced images. §9.1 says an empty pass has no filter type bytes. §9.1 says an empty pass has no filter type bytes. expected: display, conforms spec: §13.10 expected39 match 1 of 2 pixels differ3: imagesharp, imagesharp-head, upng-head	✓	✓	✓	✓	✓	!	✓	✓	✓	✓	✓	✓	✓	≠	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	≠	✓	✓	✓
y_adam7-2x2-g4png IHDRIDATIEND 2x2, interlaced, random filter per scanline; passes 2, 3, 4, 5 are empty. §8.1 says decoders are required to read interlaced images. §9.1 says an empty pass has no filter type bytes. §9.1 says an empty pass has no filter type bytes. expected: display, conforms spec: §13.10 expected40 match 4 of 4 pixels differ2: imagesharp, imagesharp-head	✓	✓	✓	✓	✓	!	✓	✓	✓	✓	✓	✓	✓	≠	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓
y_adam7-3x3-g4png IHDRIDATIEND 3x3, interlaced, random filter per scanline; passes 2, 3 are empty. §8.1 says decoders are required to read interlaced images. §9.1 says an empty pass has no filter type bytes. §9.1 says an empty pass has no filter type bytes. expected: display, conforms spec: §13.10 expected38 match 8 of 9 pixels differ2: imagesharp, imagesharp-head 3 of 9 pixels differ1: upng 1 of 9 pixels differ1: upng-head	✓	✓	✓	✓	✓	R	✓	✓	✓	✓	✓	✓	✓	≠	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	≠	≠	✓	✓	✓
y_adam7-4x4-g4png IHDRIDATIEND 4x4, interlaced, random filter per scanline; passes 2, 3 are empty. §8.1 says decoders are required to read interlaced images. §9.1 says an empty pass has no filter type bytes. §9.1 says an empty pass has no filter type bytes. expected: display, conforms spec: §13.10 expected40 match	✓	✓	✓	✓	✓	R	✓	✓	✓	✓	✓	✓	✓	R	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓
y_adam7-5x5-g4png IHDRIDATIEND 5x5, interlaced, random filter per scanline; no pass is empty. §8.1 says decoders are required to read interlaced images. expected: display, conforms spec: §13.10 expected40 match 15 of 25 pixels differ1: upng 3 of 25 pixels differ1: upng-head	✓	✓	✓	✓	✓	R	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	≠	≠	✓	✓	✓
y_adam7-1x9-g4png IHDRIDATIEND 1x9, interlaced, random filter per scanline; passes 2, 4, 6 are empty. §8.1 says decoders are required to read interlaced images. §9.1 says an empty pass has no filter type bytes. expected: display, conforms spec: §13.10 expected41 match 8 of 9 pixels differ2: imagesharp, imagesharp-head 7 of 9 pixels differ1: upng	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	≠	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	≠	✓	✓	✓	✓
y_adam7-9x1-g4png IHDRIDATIEND 9x1, interlaced, random filter per scanline; passes 3, 5, 7 are empty. §8.1 says decoders are required to read interlaced images. §9.1 says an empty pass has no filter type bytes. expected: display, conforms spec: §13.10 expected41 match 4 of 9 pixels differ1: upng-head	✓	✓	✓	✓	✓	R	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	≠	✓	✓	✓
y_adam7-2x7-g4png IHDRIDATIEND 2x7, interlaced, random filter per scanline; passes 2, 4 are empty. §8.1 says decoders are required to read interlaced images. §9.1 says an empty pass has no filter type bytes. expected: display, conforms spec: §13.10 expected39 match 4 of 14 pixels differ2: imagesharp, imagesharp-head 2 of 14 pixels differ1: upng-head	✓	✓	✓	✓	✓	R	✓	✓	✓	✓	✓	✓	✓	≠	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	≠	✓	✓	✓
y_adam7-7x2-g4png IHDRIDATIEND 7x2, interlaced, random filter per scanline; passes 3, 5 are empty. §8.1 says decoders are required to read interlaced images. §9.1 says an empty pass has no filter type bytes. expected: display, conforms spec: §13.10 expected40 match 1 of 14 pixels differ1: upng 3 of 14 pixels differ1: upng-head	✓	✓	✓	✓	✓	R	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	≠	≠	✓	✓	✓
y_adam7-8x9-g4png IHDRIDATIEND 8x9, interlaced, random filter per scanline; no pass is empty. §8.1 says decoders are required to read interlaced images. expected: display, conforms spec: §13.10 expected41 match 12 of 72 pixels differ1: upng-head	✓	✓	✓	✓	✓	R	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	≠	✓	✓	✓
y_adam7-g8png IHDRIDATIEND 13x15, interlaced, random filter per scanline; no pass is empty. §8.1 says decoders are required to read interlaced images. expected: display, conforms spec: §13.10 expected43 match 7 of 195 pixels differ1: upng-head	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	≠	✓	✓	✓
y_adam7-1x1-g8png IHDRIDATIEND 1x1, interlaced, random filter per scanline; passes 2, 3, 4, 5, 6, 7 are empty. §8.1 says decoders are required to read interlaced images. §9.1 says an empty pass has no filter type bytes. §9.1 says an empty pass has no filter type bytes. expected: display, conforms spec: §13.10 expected44 match	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓
y_adam7-1x2-g8png IHDRIDATIEND 1x2, interlaced, random filter per scanline; passes 2, 3, 4, 5, 6 are empty. §8.1 says decoders are required to read interlaced images. §9.1 says an empty pass has no filter type bytes. §9.1 says an empty pass has no filter type bytes. expected: display, conforms spec: §13.10 expected42 match 2 of 2 pixels differ2: imagesharp, imagesharp-head	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	≠	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓
y_adam7-2x1-g8png IHDRIDATIEND 2x1, interlaced, random filter per scanline; passes 2, 3, 4, 5, 7 are empty. §8.1 says decoders are required to read interlaced images. §9.1 says an empty pass has no filter type bytes. §9.1 says an empty pass has no filter type bytes. expected: display, conforms spec: §13.10 expected42 match 1 of 2 pixels differ2: imagesharp, imagesharp-head	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	≠	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓
y_adam7-2x2-g8png IHDRIDATIEND 2x2, interlaced, random filter per scanline; passes 2, 3, 4, 5 are empty. §8.1 says decoders are required to read interlaced images. §9.1 says an empty pass has no filter type bytes. §9.1 says an empty pass has no filter type bytes. expected: display, conforms spec: §13.10 expected42 match 4 of 4 pixels differ2: imagesharp, imagesharp-head	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	≠	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓
y_adam7-3x3-g8png IHDRIDATIEND 3x3, interlaced, random filter per scanline; passes 2, 3 are empty. §8.1 says decoders are required to read interlaced images. §9.1 says an empty pass has no filter type bytes. §9.1 says an empty pass has no filter type bytes. expected: display, conforms spec: §13.10 expected42 match	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	R	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓
y_adam7-4x4-g8png IHDRIDATIEND 4x4, interlaced, random filter per scanline; passes 2, 3 are empty. §8.1 says decoders are required to read interlaced images. §9.1 says an empty pass has no filter type bytes. §9.1 says an empty pass has no filter type bytes. expected: display, conforms spec: §13.10 expected42 match	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	R	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓
y_adam7-5x5-g8png IHDRIDATIEND 5x5, interlaced, random filter per scanline; no pass is empty. §8.1 says decoders are required to read interlaced images. expected: display, conforms spec: §13.10 expected43 match 1 of 25 pixels differ1: upng-head	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	≠	✓	✓	✓
y_adam7-1x9-g8png IHDRIDATIEND 1x9, interlaced, random filter per scanline; passes 2, 4, 6 are empty. §8.1 says decoders are required to read interlaced images. §9.1 says an empty pass has no filter type bytes. expected: display, conforms spec: §13.10 expected42 match 9 of 9 pixels differ2: imagesharp, imagesharp-head	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	≠	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓
y_adam7-9x1-g8png IHDRIDATIEND 9x1, interlaced, random filter per scanline; passes 3, 5, 7 are empty. §8.1 says decoders are required to read interlaced images. §9.1 says an empty pass has no filter type bytes. expected: display, conforms spec: §13.10 expected43 match 2 of 9 pixels differ1: upng-head	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	≠	✓	✓	✓
y_adam7-2x7-g8png IHDRIDATIEND 2x7, interlaced, random filter per scanline; passes 2, 4 are empty. §8.1 says decoders are required to read interlaced images. §9.1 says an empty pass has no filter type bytes. expected: display, conforms spec: §13.10 expected41 match 4 of 14 pixels differ2: imagesharp, imagesharp-head 3 of 14 pixels differ1: upng-head	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	≠	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	≠	✓	✓	✓
y_adam7-7x2-g8png IHDRIDATIEND 7x2, interlaced, random filter per scanline; passes 3, 5 are empty. §8.1 says decoders are required to read interlaced images. §9.1 says an empty pass has no filter type bytes. expected: display, conforms spec: §13.10 expected43 match 1 of 14 pixels differ1: upng-head	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	≠	✓	✓	✓
y_adam7-8x9-g8png IHDRIDATIEND 8x9, interlaced, random filter per scanline; no pass is empty. §8.1 says decoders are required to read interlaced images. expected: display, conforms spec: §13.10 expected43 match 1 of 72 pixels differ1: upng-head	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	≠	✓	✓	✓
y_adam7-g16png IHDRIDATIEND 13x15, interlaced, random filter per scanline; no pass is empty. §8.1 says decoders are required to read interlaced images. expected: display, conforms spec: §13.10 expected40 match matches the reference; 16→8 high byte3: upng, chunky_png, chunky_png-head 192 of 195 pixels differ1: upng-head	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	≠	✓	✓	✓
y_adam7-1x1-g16png IHDRIDATIEND 1x1, interlaced, random filter per scanline; passes 2, 3, 4, 5, 6, 7 are empty. §8.1 says decoders are required to read interlaced images. §9.1 says an empty pass has no filter type bytes. §9.1 says an empty pass has no filter type bytes. expected: display, conforms spec: §13.10 expected40 match matches the reference; 16→8 high byte4: upng, chunky_png, upng-head, chunky_png-head	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓
y_adam7-1x2-g16png IHDRIDATIEND 1x2, interlaced, random filter per scanline; passes 2, 3, 4, 5, 6 are empty. §8.1 says decoders are required to read interlaced images. §9.1 says an empty pass has no filter type bytes. §9.1 says an empty pass has no filter type bytes. expected: display, conforms spec: §13.10 expected38 match matches the reference; 16→8 high byte2: chunky_png, chunky_png-head 2 of 2 pixels differ2: upng, upng-head 2 of 2 pixels differ2: imagesharp, imagesharp-head	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	≠	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	≠	≠	✓	✓	✓
y_adam7-2x1-g16png IHDRIDATIEND 2x1, interlaced, random filter per scanline; passes 2, 3, 4, 5, 7 are empty. §8.1 says decoders are required to read interlaced images. §9.1 says an empty pass has no filter type bytes. §9.1 says an empty pass has no filter type bytes. expected: display, conforms spec: §13.10 expected38 match matches the reference; 16→8 high byte2: chunky_png, chunky_png-head 1 of 2 pixels differ2: imagesharp, imagesharp-head 2 of 2 pixels differ2: upng, upng-head	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	≠	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	≠	≠	✓	✓	✓
y_adam7-2x2-g16png IHDRIDATIEND 2x2, interlaced, random filter per scanline; passes 2, 3, 4, 5 are empty. §8.1 says decoders are required to read interlaced images. §9.1 says an empty pass has no filter type bytes. §9.1 says an empty pass has no filter type bytes. expected: display, conforms spec: §13.10 expected38 match 4 of 4 pixels differ2: upng, upng-head 4 of 4 pixels differ2: imagesharp, imagesharp-head matches the reference; 16→8 high byte2: chunky_png, chunky_png-head	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	≠	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	≠	≠	✓	✓	✓
y_adam7-3x3-g16png IHDRIDATIEND 3x3, interlaced, random filter per scanline; passes 2, 3 are empty. §8.1 says decoders are required to read interlaced images. §9.1 says an empty pass has no filter type bytes. §9.1 says an empty pass has no filter type bytes. expected: display, conforms spec: §13.10 expected38 match matches the reference; 16→8 high byte4: upng, chunky_png, upng-head, chunky_png-head	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	R	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓
y_adam7-4x4-g16png IHDRIDATIEND 4x4, interlaced, random filter per scanline; passes 2, 3 are empty. §8.1 says decoders are required to read interlaced images. §9.1 says an empty pass has no filter type bytes. §9.1 says an empty pass has no filter type bytes. expected: display, conforms spec: §13.10 expected38 match matches the reference; 16→8 high byte2: chunky_png, chunky_png-head 16 of 16 pixels differ1: upng-head 16 of 16 pixels differ1: upng	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	R	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	≠	≠	✓	✓	✓
y_adam7-5x5-g16png IHDRIDATIEND 5x5, interlaced, random filter per scanline; no pass is empty. §8.1 says decoders are required to read interlaced images. expected: display, conforms spec: §13.10 expected40 match matches the reference; 16→8 high byte4: upng, chunky_png, upng-head, chunky_png-head	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓
y_adam7-1x9-g16png IHDRIDATIEND 1x9, interlaced, random filter per scanline; passes 2, 4, 6 are empty. §8.1 says decoders are required to read interlaced images. §9.1 says an empty pass has no filter type bytes. expected: display, conforms spec: §13.10 expected38 match matches the reference; 16→8 high byte2: chunky_png, chunky_png-head 9 of 9 pixels differ2: imagesharp, imagesharp-head 9 of 9 pixels differ1: upng 9 of 9 pixels differ1: upng-head	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	≠	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	≠	≠	✓	✓	✓
y_adam7-9x1-g16png IHDRIDATIEND 9x1, interlaced, random filter per scanline; passes 3, 5, 7 are empty. §8.1 says decoders are required to read interlaced images. §9.1 says an empty pass has no filter type bytes. expected: display, conforms spec: §13.10 expected40 match matches the reference; 16→8 high byte3: upng, chunky_png, chunky_png-head 9 of 9 pixels differ1: upng-head	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	≠	✓	✓	✓
y_adam7-2x7-g16png IHDRIDATIEND 2x7, interlaced, random filter per scanline; passes 2, 4 are empty. §8.1 says decoders are required to read interlaced images. §9.1 says an empty pass has no filter type bytes. expected: display, conforms spec: §13.10 expected38 match 14 of 14 pixels differ2: upng, upng-head 4 of 14 pixels differ2: imagesharp, imagesharp-head matches the reference; 16→8 high byte2: chunky_png, chunky_png-head	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	≠	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	≠	≠	✓	✓	✓
y_adam7-7x2-g16png IHDRIDATIEND 7x2, interlaced, random filter per scanline; passes 3, 5 are empty. §8.1 says decoders are required to read interlaced images. §9.1 says an empty pass has no filter type bytes. expected: display, conforms spec: §13.10 expected40 match matches the reference; 16→8 high byte4: upng, chunky_png, upng-head, chunky_png-head	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓
y_adam7-8x9-g16png IHDRIDATIEND 8x9, interlaced, random filter per scanline; no pass is empty. §8.1 says decoders are required to read interlaced images. expected: display, conforms spec: §13.10 expected40 match matches the reference; 16→8 high byte3: upng, chunky_png, chunky_png-head 72 of 72 pixels differ1: upng-head	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	≠	✓	✓	✓
y_adam7-rgb8png IHDRIDATIEND 13x15, interlaced, random filter per scanline; no pass is empty. §8.1 says decoders are required to read interlaced images. expected: display, conforms spec: §13.10 expected43 match 6 of 195 pixels differ1: upng-head	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	≠	✓	✓	✓
y_adam7-1x1-rgb8png IHDRIDATIEND 1x1, interlaced, random filter per scanline; passes 2, 3, 4, 5, 6, 7 are empty. §8.1 says decoders are required to read interlaced images. §9.1 says an empty pass has no filter type bytes. §9.1 says an empty pass has no filter type bytes. expected: display, conforms spec: §13.10 expected44 match	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓
y_adam7-1x2-rgb8png IHDRIDATIEND 1x2, interlaced, random filter per scanline; passes 2, 3, 4, 5, 6 are empty. §8.1 says decoders are required to read interlaced images. §9.1 says an empty pass has no filter type bytes. §9.1 says an empty pass has no filter type bytes. expected: display, conforms spec: §13.10 expected40 match 2 of 2 pixels differ2: imagesharp, imagesharp-head 1 of 2 pixels differ1: upng 1 of 2 pixels differ1: upng-head	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	≠	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	≠	≠	✓	✓	✓
y_adam7-2x1-rgb8png IHDRIDATIEND 2x1, interlaced, random filter per scanline; passes 2, 3, 4, 5, 7 are empty. §8.1 says decoders are required to read interlaced images. §9.1 says an empty pass has no filter type bytes. §9.1 says an empty pass has no filter type bytes. expected: display, conforms spec: §13.10 expected40 match 1 of 2 pixels differ2: imagesharp, imagesharp-head 1 of 2 pixels differ1: upng-head 1 of 2 pixels differ1: upng	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	≠	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	≠	≠	✓	✓	✓
y_adam7-2x2-rgb8png IHDRIDATIEND 2x2, interlaced, random filter per scanline; passes 2, 3, 4, 5 are empty. §8.1 says decoders are required to read interlaced images. §9.1 says an empty pass has no filter type bytes. §9.1 says an empty pass has no filter type bytes. expected: display, conforms spec: §13.10 expected40 match 4 of 4 pixels differ2: imagesharp, imagesharp-head 1 of 4 pixels differ1: upng 1 of 4 pixels differ1: upng-head	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	≠	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	≠	≠	✓	✓	✓
y_adam7-3x3-rgb8png IHDRIDATIEND 3x3, interlaced, random filter per scanline; passes 2, 3 are empty. §8.1 says decoders are required to read interlaced images. §9.1 says an empty pass has no filter type bytes. §9.1 says an empty pass has no filter type bytes. expected: display, conforms spec: §13.10 expected42 match	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	R	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓
y_adam7-4x4-rgb8png IHDRIDATIEND 4x4, interlaced, random filter per scanline; passes 2, 3 are empty. §8.1 says decoders are required to read interlaced images. §9.1 says an empty pass has no filter type bytes. §9.1 says an empty pass has no filter type bytes. expected: display, conforms spec: §13.10 expected42 match	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	R	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓
y_adam7-5x5-rgb8png IHDRIDATIEND 5x5, interlaced, random filter per scanline; no pass is empty. §8.1 says decoders are required to read interlaced images. expected: display, conforms spec: §13.10 expected43 match 1 of 25 pixels differ1: upng-head	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	≠	✓	✓	✓
y_adam7-1x9-rgb8png IHDRIDATIEND 1x9, interlaced, random filter per scanline; passes 2, 4, 6 are empty. §8.1 says decoders are required to read interlaced images. §9.1 says an empty pass has no filter type bytes. expected: display, conforms spec: §13.10 expected40 match 9 of 9 pixels differ2: imagesharp, imagesharp-head 5 of 9 pixels differ1: upng-head 5 of 9 pixels differ1: upng	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	≠	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	≠	≠	✓	✓	✓
y_adam7-9x1-rgb8png IHDRIDATIEND 9x1, interlaced, random filter per scanline; passes 3, 5, 7 are empty. §8.1 says decoders are required to read interlaced images. §9.1 says an empty pass has no filter type bytes. expected: display, conforms spec: §13.10 expected43 match 1 of 9 pixels differ1: upng-head	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	≠	✓	✓	✓
y_adam7-2x7-rgb8png IHDRIDATIEND 2x7, interlaced, random filter per scanline; passes 2, 4 are empty. §8.1 says decoders are required to read interlaced images. §9.1 says an empty pass has no filter type bytes. expected: display, conforms spec: §13.10 expected40 match 4 of 14 pixels differ2: imagesharp, imagesharp-head 2 of 14 pixels differ1: upng-head 2 of 14 pixels differ1: upng	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	≠	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	≠	≠	✓	✓	✓
y_adam7-7x2-rgb8png IHDRIDATIEND 7x2, interlaced, random filter per scanline; passes 3, 5 are empty. §8.1 says decoders are required to read interlaced images. §9.1 says an empty pass has no filter type bytes. expected: display, conforms spec: §13.10 expected43 match 1 of 14 pixels differ1: upng-head	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	≠	✓	✓	✓
y_adam7-8x9-rgb8png IHDRIDATIEND 8x9, interlaced, random filter per scanline; no pass is empty. §8.1 says decoders are required to read interlaced images. expected: display, conforms spec: §13.10 expected43 match 22 of 72 pixels differ1: upng-head	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	≠	✓	✓	✓
y_adam7-rgb16png IHDRIDATIEND 13x15, interlaced, random filter per scanline; no pass is empty. §8.1 says decoders are required to read interlaced images. expected: display, conforms spec: §13.10 expected38 match matches the reference; 16→8 high byte6: upng, pillow, chunky_png, upng-head, pillow-head, chunky_png-head	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓
y_adam7-1x1-rgb16png IHDRIDATIEND 1x1, interlaced, random filter per scanline; passes 2, 3, 4, 5, 6, 7 are empty. §8.1 says decoders are required to read interlaced images. §9.1 says an empty pass has no filter type bytes. §9.1 says an empty pass has no filter type bytes. expected: display, conforms spec: §13.10 expected38 match matches the reference; 16→8 high byte6: upng, pillow, chunky_png, upng-head, pillow-head, chunky_png-head	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓
y_adam7-1x2-rgb16png IHDRIDATIEND 1x2, interlaced, random filter per scanline; passes 2, 3, 4, 5, 6 are empty. §8.1 says decoders are required to read interlaced images. §9.1 says an empty pass has no filter type bytes. §9.1 says an empty pass has no filter type bytes. expected: display, conforms spec: §13.10 expected36 match matches the reference; 16→8 high byte6: upng, pillow, chunky_png, upng-head, pillow-head, chunky_png-head 2 of 2 pixels differ2: imagesharp, imagesharp-head	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	≠	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓
y_adam7-2x1-rgb16png IHDRIDATIEND 2x1, interlaced, random filter per scanline; passes 2, 3, 4, 5, 7 are empty. §8.1 says decoders are required to read interlaced images. §9.1 says an empty pass has no filter type bytes. §9.1 says an empty pass has no filter type bytes. expected: display, conforms spec: §13.10 expected36 match matches the reference; 16→8 high byte5: pillow, chunky_png, upng-head, pillow-head, chunky_png-head 1 of 2 pixels differ2: imagesharp, imagesharp-head 2 of 2 pixels differ1: upng	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	≠	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	≠	✓	✓	✓	✓
y_adam7-2x2-rgb16png IHDRIDATIEND 2x2, interlaced, random filter per scanline; passes 2, 3, 4, 5 are empty. §8.1 says decoders are required to read interlaced images. §9.1 says an empty pass has no filter type bytes. §9.1 says an empty pass has no filter type bytes. expected: display, conforms spec: §13.10 expected36 match matches the reference; 16→8 high byte5: pillow, chunky_png, upng-head, pillow-head, chunky_png-head 4 of 4 pixels differ2: imagesharp, imagesharp-head 4 of 4 pixels differ1: upng	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	≠	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	≠	✓	✓	✓	✓
y_adam7-3x3-rgb16png IHDRIDATIEND 3x3, interlaced, random filter per scanline; passes 2, 3 are empty. §8.1 says decoders are required to read interlaced images. §9.1 says an empty pass has no filter type bytes. §9.1 says an empty pass has no filter type bytes. expected: display, conforms spec: §13.10 expected36 match matches the reference; 16→8 high byte5: pillow, chunky_png, upng-head, pillow-head, chunky_png-head 9 of 9 pixels differ1: upng	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	R	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	≠	✓	✓	✓	✓
y_adam7-4x4-rgb16png IHDRIDATIEND 4x4, interlaced, random filter per scanline; passes 2, 3 are empty. §8.1 says decoders are required to read interlaced images. §9.1 says an empty pass has no filter type bytes. §9.1 says an empty pass has no filter type bytes. expected: display, conforms spec: §13.10 expected36 match matches the reference; 16→8 high byte4: pillow, chunky_png, pillow-head, chunky_png-head 16 of 16 pixels differ1: upng-head 16 of 16 pixels differ1: upng	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	R	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	≠	≠	✓	✓	✓
y_adam7-5x5-rgb16png IHDRIDATIEND 5x5, interlaced, random filter per scanline; no pass is empty. §8.1 says decoders are required to read interlaced images. expected: display, conforms spec: §13.10 expected38 match matches the reference; 16→8 high byte5: upng, pillow, chunky_png, pillow-head, chunky_png-head 24 of 25 pixels differ1: upng-head	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	≠	✓	✓	✓
y_adam7-1x9-rgb16png IHDRIDATIEND 1x9, interlaced, random filter per scanline; passes 2, 4, 6 are empty. §8.1 says decoders are required to read interlaced images. §9.1 says an empty pass has no filter type bytes. expected: display, conforms spec: §13.10 expected36 match matches the reference; 16→8 high byte4: pillow, chunky_png, pillow-head, chunky_png-head 9 of 9 pixels differ2: imagesharp, imagesharp-head 9 of 9 pixels differ1: upng 9 of 9 pixels differ1: upng-head	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	≠	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	≠	≠	✓	✓	✓
y_adam7-9x1-rgb16png IHDRIDATIEND 9x1, interlaced, random filter per scanline; passes 3, 5, 7 are empty. §8.1 says decoders are required to read interlaced images. §9.1 says an empty pass has no filter type bytes. expected: display, conforms spec: §13.10 expected38 match matches the reference; 16→8 high byte5: upng, pillow, chunky_png, pillow-head, chunky_png-head 9 of 9 pixels differ1: upng-head	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	≠	✓	✓	✓
y_adam7-2x7-rgb16png IHDRIDATIEND 2x7, interlaced, random filter per scanline; passes 2, 4 are empty. §8.1 says decoders are required to read interlaced images. §9.1 says an empty pass has no filter type bytes. expected: display, conforms spec: §13.10 expected36 match matches the reference; 16→8 high byte4: pillow, chunky_png, pillow-head, chunky_png-head 4 of 14 pixels differ2: imagesharp, imagesharp-head 14 of 14 pixels differ1: upng-head 14 of 14 pixels differ1: upng	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	≠	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	≠	≠	✓	✓	✓
y_adam7-7x2-rgb16png IHDRIDATIEND 7x2, interlaced, random filter per scanline; passes 3, 5 are empty. §8.1 says decoders are required to read interlaced images. §9.1 says an empty pass has no filter type bytes. expected: display, conforms spec: §13.10 expected38 match matches the reference; 16→8 high byte5: upng, pillow, chunky_png, pillow-head, chunky_png-head 14 of 14 pixels differ1: upng-head	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	≠	✓	✓	✓
y_adam7-8x9-rgb16png IHDRIDATIEND 8x9, interlaced, random filter per scanline; no pass is empty. §8.1 says decoders are required to read interlaced images. expected: display, conforms spec: §13.10 expected38 match matches the reference; 16→8 high byte5: upng, pillow, chunky_png, pillow-head, chunky_png-head 71 of 72 pixels differ1: upng-head	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	≠	✓	✓	✓
y_adam7-p1png IHDRPLTEIDATIEND 13x15, interlaced, random filter per scanline; no pass is empty. §8.1 says decoders are required to read interlaced images. expected: display, conforms spec: §13.10 expected40 match 6 of 195 pixels differ1: upng-head 49 of 195 pixels differ1: upng	✓	✓	✓	✓	✓	R	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	≠	≠	✓	✓	✓
y_adam7-1x1-p1png IHDRPLTEIDATIEND 1x1, interlaced, random filter per scanline; passes 2, 3, 4, 5, 6, 7 are empty. §8.1 says decoders are required to read interlaced images. §9.1 says an empty pass has no filter type bytes. §9.1 says an empty pass has no filter type bytes. expected: display, conforms spec: §13.10 expected44 match	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓
y_adam7-1x2-p1png IHDRPLTEIDATIEND 1x2, interlaced, random filter per scanline; passes 2, 3, 4, 5, 6 are empty. §8.1 says decoders are required to read interlaced images. §9.1 says an empty pass has no filter type bytes. §9.1 says an empty pass has no filter type bytes. expected: display, conforms spec: §13.10 expected42 match 1 of 2 pixels differ2: imagesharp, imagesharp-head	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	≠	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓
y_adam7-2x1-p1png IHDRPLTEIDATIEND 2x1, interlaced, random filter per scanline; passes 2, 3, 4, 5, 7 are empty. §8.1 says decoders are required to read interlaced images. §9.1 says an empty pass has no filter type bytes. §9.1 says an empty pass has no filter type bytes. expected: display, conforms spec: §13.10 expected40 match 1 of 2 pixels differ2: imagesharp, imagesharp-head	✓	✓	✓	✓	✓	!	✓	✓	✓	✓	✓	✓	✓	≠	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓
y_adam7-2x2-p1png IHDRPLTEIDATIEND 2x2, interlaced, random filter per scanline; passes 2, 3, 4, 5 are empty. §8.1 says decoders are required to read interlaced images. §9.1 says an empty pass has no filter type bytes. §9.1 says an empty pass has no filter type bytes. expected: display, conforms spec: §13.10 expected40 match 3 of 4 pixels differ2: imagesharp, imagesharp-head	✓	✓	✓	✓	✓	!	✓	✓	✓	✓	✓	✓	✓	≠	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓
y_adam7-3x3-p1png IHDRPLTEIDATIEND 3x3, interlaced, random filter per scanline; passes 2, 3 are empty. §8.1 says decoders are required to read interlaced images. §9.1 says an empty pass has no filter type bytes. §9.1 says an empty pass has no filter type bytes. expected: display, conforms spec: §13.10 expected40 match 3 of 9 pixels differ2: imagesharp, imagesharp-head	✓	✓	✓	✓	✓	!	✓	✓	✓	✓	✓	✓	✓	≠	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓
y_adam7-4x4-p1png IHDRPLTEIDATIEND 4x4, interlaced, random filter per scanline; passes 2, 3 are empty. §8.1 says decoders are required to read interlaced images. §9.1 says an empty pass has no filter type bytes. §9.1 says an empty pass has no filter type bytes. expected: display, conforms spec: §13.10 expected39 match 7 of 16 pixels differ2: imagesharp, imagesharp-head 2 of 16 pixels differ1: upng-head	✓	✓	✓	✓	✓	R	✓	✓	✓	✓	✓	✓	✓	≠	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	≠	✓	✓	✓
y_adam7-5x5-p1png IHDRPLTEIDATIEND 5x5, interlaced, random filter per scanline; no pass is empty. §8.1 says decoders are required to read interlaced images. expected: display, conforms spec: §13.10 expected40 match 6 of 25 pixels differ1: upng-head 5 of 25 pixels differ1: upng	✓	✓	✓	✓	✓	R	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	≠	≠	✓	✓	✓
y_adam7-1x9-p1png IHDRPLTEIDATIEND 1x9, interlaced, random filter per scanline; passes 2, 4, 6 are empty. §8.1 says decoders are required to read interlaced images. §9.1 says an empty pass has no filter type bytes. expected: display, conforms spec: §13.10 expected42 match 9 of 9 pixels differ2: imagesharp, imagesharp-head	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	≠	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓
y_adam7-9x1-p1png IHDRPLTEIDATIEND 9x1, interlaced, random filter per scanline; passes 3, 5, 7 are empty. §8.1 says decoders are required to read interlaced images. §9.1 says an empty pass has no filter type bytes. expected: display, conforms spec: §13.10 expected42 match	✓	✓	✓	✓	✓	R	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓
y_adam7-2x7-p1png IHDRPLTEIDATIEND 2x7, interlaced, random filter per scanline; passes 2, 4 are empty. §8.1 says decoders are required to read interlaced images. §9.1 says an empty pass has no filter type bytes. expected: display, conforms spec: §13.10 expected39 match 2 of 14 pixels differ2: imagesharp, imagesharp-head 2 of 14 pixels differ1: upng-head	✓	✓	✓	✓	✓	R	✓	✓	✓	✓	✓	✓	✓	≠	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	≠	✓	✓	✓
y_adam7-7x2-p1png IHDRPLTEIDATIEND 7x2, interlaced, random filter per scanline; passes 3, 5 are empty. §8.1 says decoders are required to read interlaced images. §9.1 says an empty pass has no filter type bytes. expected: display, conforms spec: §13.10 expected42 match	✓	✓	✓	✓	✓	R	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓
y_adam7-8x9-p1png IHDRPLTEIDATIEND 8x9, interlaced, random filter per scanline; no pass is empty. §8.1 says decoders are required to read interlaced images. expected: display, conforms spec: §13.10 expected40 match 29 of 72 pixels differ1: upng-head 29 of 72 pixels differ1: upng	✓	✓	✓	✓	✓	R	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	≠	≠	✓	✓	✓
y_adam7-p2png IHDRPLTEIDATIEND 13x15, interlaced, random filter per scanline; no pass is empty. §8.1 says decoders are required to read interlaced images. expected: display, conforms spec: §13.10 expected41 match 1 of 195 pixels differ1: upng-head	✓	✓	✓	✓	✓	R	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	≠	✓	✓	✓
y_adam7-1x1-p2png IHDRPLTEIDATIEND 1x1, interlaced, random filter per scanline; passes 2, 3, 4, 5, 6, 7 are empty. §8.1 says decoders are required to read interlaced images. §9.1 says an empty pass has no filter type bytes. §9.1 says an empty pass has no filter type bytes. expected: display, conforms spec: §13.10 expected44 match	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓
y_adam7-1x2-p2png IHDRPLTEIDATIEND 1x2, interlaced, random filter per scanline; passes 2, 3, 4, 5, 6 are empty. §8.1 says decoders are required to read interlaced images. §9.1 says an empty pass has no filter type bytes. §9.1 says an empty pass has no filter type bytes. expected: display, conforms spec: §13.10 expected42 match 1 of 2 pixels differ2: imagesharp, imagesharp-head	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	≠	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓
y_adam7-2x1-p2png IHDRPLTEIDATIEND 2x1, interlaced, random filter per scanline; passes 2, 3, 4, 5, 7 are empty. §8.1 says decoders are required to read interlaced images. §9.1 says an empty pass has no filter type bytes. §9.1 says an empty pass has no filter type bytes. expected: display, conforms spec: §13.10 expected40 match 1 of 2 pixels differ2: imagesharp, imagesharp-head	✓	✓	✓	✓	✓	!	✓	✓	✓	✓	✓	✓	✓	≠	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓
y_adam7-2x2-p2png IHDRPLTEIDATIEND 2x2, interlaced, random filter per scanline; passes 2, 3, 4, 5 are empty. §8.1 says decoders are required to read interlaced images. §9.1 says an empty pass has no filter type bytes. §9.1 says an empty pass has no filter type bytes. expected: display, conforms spec: §13.10 expected40 match 3 of 4 pixels differ2: imagesharp, imagesharp-head	✓	✓	✓	✓	✓	!	✓	✓	✓	✓	✓	✓	✓	≠	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓
y_adam7-3x3-p2png IHDRPLTEIDATIEND 3x3, interlaced, random filter per scanline; passes 2, 3 are empty. §8.1 says decoders are required to read interlaced images. §9.1 says an empty pass has no filter type bytes. §9.1 says an empty pass has no filter type bytes. expected: display, conforms spec: §13.10 expected40 match 3 of 9 pixels differ2: imagesharp, imagesharp-head	✓	✓	✓	✓	✓	!	✓	✓	✓	✓	✓	✓	✓	≠	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓
y_adam7-4x4-p2png IHDRPLTEIDATIEND 4x4, interlaced, random filter per scanline; passes 2, 3 are empty. §8.1 says decoders are required to read interlaced images. §9.1 says an empty pass has no filter type bytes. §9.1 says an empty pass has no filter type bytes. expected: display, conforms spec: §13.10 expected39 match 8 of 16 pixels differ2: imagesharp, imagesharp-head 2 of 16 pixels differ1: upng-head	✓	✓	✓	✓	✓	R	✓	✓	✓	✓	✓	✓	✓	≠	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	≠	✓	✓	✓
y_adam7-5x5-p2png IHDRPLTEIDATIEND 5x5, interlaced, random filter per scanline; no pass is empty. §8.1 says decoders are required to read interlaced images. expected: display, conforms spec: §13.10 expected41 match 3 of 25 pixels differ1: upng-head	✓	✓	✓	✓	✓	R	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	≠	✓	✓	✓
y_adam7-1x9-p2png IHDRPLTEIDATIEND 1x9, interlaced, random filter per scanline; passes 2, 4, 6 are empty. §8.1 says decoders are required to read interlaced images. §9.1 says an empty pass has no filter type bytes. expected: display, conforms spec: §13.10 expected42 match 9 of 9 pixels differ2: imagesharp, imagesharp-head	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	≠	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓
y_adam7-9x1-p2png IHDRPLTEIDATIEND 9x1, interlaced, random filter per scanline; passes 3, 5, 7 are empty. §8.1 says decoders are required to read interlaced images. §9.1 says an empty pass has no filter type bytes. expected: display, conforms spec: §13.10 expected42 match	✓	✓	✓	✓	✓	R	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓
y_adam7-2x7-p2png IHDRPLTEIDATIEND 2x7, interlaced, random filter per scanline; passes 2, 4 are empty. §8.1 says decoders are required to read interlaced images. §9.1 says an empty pass has no filter type bytes. expected: display, conforms spec: §13.10 expected39 match 3 of 14 pixels differ2: imagesharp, imagesharp-head 2 of 14 pixels differ1: upng-head	✓	✓	✓	✓	✓	R	✓	✓	✓	✓	✓	✓	✓	≠	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	≠	✓	✓	✓
y_adam7-7x2-p2png IHDRPLTEIDATIEND 7x2, interlaced, random filter per scanline; passes 3, 5 are empty. §8.1 says decoders are required to read interlaced images. §9.1 says an empty pass has no filter type bytes. expected: display, conforms spec: §13.10 expected42 match	✓	✓	✓	✓	✓	R	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓
y_adam7-8x9-p2png IHDRPLTEIDATIEND 8x9, interlaced, random filter per scanline; no pass is empty. §8.1 says decoders are required to read interlaced images. expected: display, conforms spec: §13.10 expected41 match 16 of 72 pixels differ1: upng-head	✓	✓	✓	✓	✓	R	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	≠	✓	✓	✓
y_adam7-p4png IHDRPLTEIDATIEND 13x15, interlaced, random filter per scanline; no pass is empty. §8.1 says decoders are required to read interlaced images. expected: display, conforms spec: §13.10 expected41 match 10 of 195 pixels differ1: upng-head	✓	✓	✓	✓	✓	R	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	≠	✓	✓	✓
y_adam7-1x1-p4png IHDRPLTEIDATIEND 1x1, interlaced, random filter per scanline; passes 2, 3, 4, 5, 6, 7 are empty. §8.1 says decoders are required to read interlaced images. §9.1 says an empty pass has no filter type bytes. §9.1 says an empty pass has no filter type bytes. expected: display, conforms spec: §13.10 expected44 match	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓
y_adam7-1x2-p4png IHDRPLTEIDATIEND 1x2, interlaced, random filter per scanline; passes 2, 3, 4, 5, 6 are empty. §8.1 says decoders are required to read interlaced images. §9.1 says an empty pass has no filter type bytes. §9.1 says an empty pass has no filter type bytes. expected: display, conforms spec: §13.10 expected42 match 2 of 2 pixels differ2: imagesharp, imagesharp-head	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	≠	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓
y_adam7-2x1-p4png IHDRPLTEIDATIEND 2x1, interlaced, random filter per scanline; passes 2, 3, 4, 5, 7 are empty. §8.1 says decoders are required to read interlaced images. §9.1 says an empty pass has no filter type bytes. §9.1 says an empty pass has no filter type bytes. expected: display, conforms spec: §13.10 expected39 match 1 of 2 pixels differ2: imagesharp, imagesharp-head 1 of 2 pixels differ1: upng-head	✓	✓	✓	✓	✓	!	✓	✓	✓	✓	✓	✓	✓	≠	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	≠	✓	✓	✓
y_adam7-2x2-p4png IHDRPLTEIDATIEND 2x2, interlaced, random filter per scanline; passes 2, 3, 4, 5 are empty. §8.1 says decoders are required to read interlaced images. §9.1 says an empty pass has no filter type bytes. §9.1 says an empty pass has no filter type bytes. expected: display, conforms spec: §13.10 expected40 match 4 of 4 pixels differ2: imagesharp, imagesharp-head	✓	✓	✓	✓	✓	!	✓	✓	✓	✓	✓	✓	✓	≠	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓
y_adam7-3x3-p4png IHDRPLTEIDATIEND 3x3, interlaced, random filter per scanline; passes 2, 3 are empty. §8.1 says decoders are required to read interlaced images. §9.1 says an empty pass has no filter type bytes. §9.1 says an empty pass has no filter type bytes. expected: display, conforms spec: §13.10 expected39 match 8 of 9 pixels differ2: imagesharp, imagesharp-head 1 of 9 pixels differ1: upng-head	✓	✓	✓	✓	✓	R	✓	✓	✓	✓	✓	✓	✓	≠	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	≠	✓	✓	✓
y_adam7-4x4-p4png IHDRPLTEIDATIEND 4x4, interlaced, random filter per scanline; passes 2, 3 are empty. §8.1 says decoders are required to read interlaced images. §9.1 says an empty pass has no filter type bytes. §9.1 says an empty pass has no filter type bytes. expected: display, conforms spec: §13.10 expected40 match 15 of 16 pixels differ2: imagesharp, imagesharp-head	✓	✓	✓	✓	✓	R	✓	✓	✓	✓	✓	✓	✓	≠	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓
y_adam7-5x5-p4png IHDRPLTEIDATIEND 5x5, interlaced, random filter per scanline; no pass is empty. §8.1 says decoders are required to read interlaced images. expected: display, conforms spec: §13.10 expected41 match 3 of 25 pixels differ1: upng-head	✓	✓	✓	✓	✓	R	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	≠	✓	✓	✓
y_adam7-1x9-p4png IHDRPLTEIDATIEND 1x9, interlaced, random filter per scanline; passes 2, 4, 6 are empty. §8.1 says decoders are required to read interlaced images. §9.1 says an empty pass has no filter type bytes. expected: display, conforms spec: §13.10 expected42 match 9 of 9 pixels differ2: imagesharp, imagesharp-head	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	≠	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓
y_adam7-9x1-p4png IHDRPLTEIDATIEND 9x1, interlaced, random filter per scanline; passes 3, 5, 7 are empty. §8.1 says decoders are required to read interlaced images. §9.1 says an empty pass has no filter type bytes. expected: display, conforms spec: §13.10 expected41 match 4 of 9 pixels differ1: upng-head	✓	✓	✓	✓	✓	R	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	≠	✓	✓	✓
y_adam7-2x7-p4png IHDRPLTEIDATIEND 2x7, interlaced, random filter per scanline; passes 2, 4 are empty. §8.1 says decoders are required to read interlaced images. §9.1 says an empty pass has no filter type bytes. expected: display, conforms spec: §13.10 expected39 match 4 of 14 pixels differ2: imagesharp, imagesharp-head 2 of 14 pixels differ1: upng-head	✓	✓	✓	✓	✓	R	✓	✓	✓	✓	✓	✓	✓	≠	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	≠	✓	✓	✓
y_adam7-7x2-p4png IHDRPLTEIDATIEND 7x2, interlaced, random filter per scanline; passes 3, 5 are empty. §8.1 says decoders are required to read interlaced images. §9.1 says an empty pass has no filter type bytes. expected: display, conforms spec: §13.10 expected41 match 5 of 14 pixels differ1: upng-head	✓	✓	✓	✓	✓	R	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	≠	✓	✓	✓
y_adam7-8x9-p4png IHDRPLTEIDATIEND 8x9, interlaced, random filter per scanline; no pass is empty. §8.1 says decoders are required to read interlaced images. expected: display, conforms spec: §13.10 expected41 match 6 of 72 pixels differ1: upng-head	✓	✓	✓	✓	✓	R	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	≠	✓	✓	✓
y_adam7-p8png IHDRPLTEIDATIEND 13x15, interlaced, random filter per scanline; no pass is empty. §8.1 says decoders are required to read interlaced images. expected: display, conforms spec: §13.10 expected43 match 6 of 195 pixels differ1: upng-head	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	≠	✓	✓	✓
y_adam7-1x1-p8png IHDRPLTEIDATIEND 1x1, interlaced, random filter per scanline; passes 2, 3, 4, 5, 6, 7 are empty. §8.1 says decoders are required to read interlaced images. §9.1 says an empty pass has no filter type bytes. §9.1 says an empty pass has no filter type bytes. expected: display, conforms spec: §13.10 expected44 match	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓
y_adam7-1x2-p8png IHDRPLTEIDATIEND 1x2, interlaced, random filter per scanline; passes 2, 3, 4, 5, 6 are empty. §8.1 says decoders are required to read interlaced images. §9.1 says an empty pass has no filter type bytes. §9.1 says an empty pass has no filter type bytes. expected: display, conforms spec: §13.10 expected42 match 2 of 2 pixels differ2: imagesharp, imagesharp-head	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	≠	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓
y_adam7-2x1-p8png IHDRPLTEIDATIEND 2x1, interlaced, random filter per scanline; passes 2, 3, 4, 5, 7 are empty. §8.1 says decoders are required to read interlaced images. §9.1 says an empty pass has no filter type bytes. §9.1 says an empty pass has no filter type bytes. expected: display, conforms spec: §13.10 expected42 match 1 of 2 pixels differ2: imagesharp, imagesharp-head	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	≠	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓
y_adam7-2x2-p8png IHDRPLTEIDATIEND 2x2, interlaced, random filter per scanline; passes 2, 3, 4, 5 are empty. §8.1 says decoders are required to read interlaced images. §9.1 says an empty pass has no filter type bytes. §9.1 says an empty pass has no filter type bytes. expected: display, conforms spec: §13.10 expected42 match 4 of 4 pixels differ2: imagesharp, imagesharp-head	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	≠	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓
y_adam7-3x3-p8png IHDRPLTEIDATIEND 3x3, interlaced, random filter per scanline; passes 2, 3 are empty. §8.1 says decoders are required to read interlaced images. §9.1 says an empty pass has no filter type bytes. §9.1 says an empty pass has no filter type bytes. expected: display, conforms spec: §13.10 expected42 match 8 of 9 pixels differ2: imagesharp, imagesharp-head	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	≠	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓
y_adam7-4x4-p8png IHDRPLTEIDATIEND 4x4, interlaced, random filter per scanline; passes 2, 3 are empty. §8.1 says decoders are required to read interlaced images. §9.1 says an empty pass has no filter type bytes. §9.1 says an empty pass has no filter type bytes. expected: display, conforms spec: §13.10 expected42 match 14 of 16 pixels differ2: imagesharp, imagesharp-head	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	≠	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓
y_adam7-5x5-p8png IHDRPLTEIDATIEND 5x5, interlaced, random filter per scanline; no pass is empty. §8.1 says decoders are required to read interlaced images. expected: display, conforms spec: §13.10 expected43 match 2 of 25 pixels differ1: upng-head	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	≠	✓	✓	✓
y_adam7-1x9-p8png IHDRPLTEIDATIEND 1x9, interlaced, random filter per scanline; passes 2, 4, 6 are empty. §8.1 says decoders are required to read interlaced images. §9.1 says an empty pass has no filter type bytes. expected: display, conforms spec: §13.10 expected42 match 9 of 9 pixels differ2: imagesharp, imagesharp-head	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	≠	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓
y_adam7-9x1-p8png IHDRPLTEIDATIEND 9x1, interlaced, random filter per scanline; passes 3, 5, 7 are empty. §8.1 says decoders are required to read interlaced images. §9.1 says an empty pass has no filter type bytes. expected: display, conforms spec: §13.10 expected44 match	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓
y_adam7-2x7-p8png IHDRPLTEIDATIEND 2x7, interlaced, random filter per scanline; passes 2, 4 are empty. §8.1 says decoders are required to read interlaced images. §9.1 says an empty pass has no filter type bytes. expected: display, conforms spec: §13.10 expected42 match 4 of 14 pixels differ2: imagesharp, imagesharp-head	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	≠	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓
y_adam7-7x2-p8png IHDRPLTEIDATIEND 7x2, interlaced, random filter per scanline; passes 3, 5 are empty. §8.1 says decoders are required to read interlaced images. §9.1 says an empty pass has no filter type bytes. expected: display, conforms spec: §13.10 expected43 match 1 of 14 pixels differ1: upng-head	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	≠	✓	✓	✓
y_adam7-8x9-p8png IHDRPLTEIDATIEND 8x9, interlaced, random filter per scanline; no pass is empty. §8.1 says decoders are required to read interlaced images. expected: display, conforms spec: §13.10 expected43 match 2 of 72 pixels differ1: upng-head	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	≠	✓	✓	✓
y_adam7-ga8png IHDRIDATIEND 13x15, interlaced, random filter per scanline; no pass is empty. §8.1 says decoders are required to read interlaced images. expected: display, conforms spec: §13.10 expected43 match 14 of 195 pixels differ1: upng-head	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	≠	✓	✓	✓
y_adam7-1x1-ga8png IHDRIDATIEND 1x1, interlaced, random filter per scanline; passes 2, 3, 4, 5, 6, 7 are empty. §8.1 says decoders are required to read interlaced images. §9.1 says an empty pass has no filter type bytes. §9.1 says an empty pass has no filter type bytes. expected: display, conforms spec: §13.10 expected44 match	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓
y_adam7-1x2-ga8png IHDRIDATIEND 1x2, interlaced, random filter per scanline; passes 2, 3, 4, 5, 6 are empty. §8.1 says decoders are required to read interlaced images. §9.1 says an empty pass has no filter type bytes. §9.1 says an empty pass has no filter type bytes. expected: display, conforms spec: §13.10 expected40 match 2 of 2 pixels differ2: imagesharp, imagesharp-head 1 of 2 pixels differ2: upng, upng-head	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	≠	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	≠	≠	✓	✓	✓
y_adam7-2x1-ga8png IHDRIDATIEND 2x1, interlaced, random filter per scanline; passes 2, 3, 4, 5, 7 are empty. §8.1 says decoders are required to read interlaced images. §9.1 says an empty pass has no filter type bytes. §9.1 says an empty pass has no filter type bytes. expected: display, conforms spec: §13.10 expected42 match 1 of 2 pixels differ2: imagesharp, imagesharp-head	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	≠	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓
y_adam7-2x2-ga8png IHDRIDATIEND 2x2, interlaced, random filter per scanline; passes 2, 3, 4, 5 are empty. §8.1 says decoders are required to read interlaced images. §9.1 says an empty pass has no filter type bytes. §9.1 says an empty pass has no filter type bytes. expected: display, conforms spec: §13.10 expected40 match 1 of 4 pixels differ2: upng, upng-head 4 of 4 pixels differ2: imagesharp, imagesharp-head	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	≠	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	≠	≠	✓	✓	✓
y_adam7-3x3-ga8png IHDRIDATIEND 3x3, interlaced, random filter per scanline; passes 2, 3 are empty. §8.1 says decoders are required to read interlaced images. §9.1 says an empty pass has no filter type bytes. §9.1 says an empty pass has no filter type bytes. expected: display, conforms spec: §13.10 expected40 match 1 of 9 pixels differ2: upng, upng-head	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	R	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	≠	≠	✓	✓	✓
y_adam7-4x4-ga8png IHDRIDATIEND 4x4, interlaced, random filter per scanline; passes 2, 3 are empty. §8.1 says decoders are required to read interlaced images. §9.1 says an empty pass has no filter type bytes. §9.1 says an empty pass has no filter type bytes. expected: display, conforms spec: §13.10 expected42 match	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	R	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓
y_adam7-5x5-ga8png IHDRIDATIEND 5x5, interlaced, random filter per scanline; no pass is empty. §8.1 says decoders are required to read interlaced images. expected: display, conforms spec: §13.10 expected43 match 2 of 25 pixels differ1: upng-head	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	≠	✓	✓	✓
y_adam7-1x9-ga8png IHDRIDATIEND 1x9, interlaced, random filter per scanline; passes 2, 4, 6 are empty. §8.1 says decoders are required to read interlaced images. §9.1 says an empty pass has no filter type bytes. expected: display, conforms spec: §13.10 expected40 match 9 of 9 pixels differ2: imagesharp, imagesharp-head 3 of 9 pixels differ1: upng 4 of 9 pixels differ1: upng-head	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	≠	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	≠	≠	✓	✓	✓
y_adam7-9x1-ga8png IHDRIDATIEND 9x1, interlaced, random filter per scanline; passes 3, 5, 7 are empty. §8.1 says decoders are required to read interlaced images. §9.1 says an empty pass has no filter type bytes. expected: display, conforms spec: §13.10 expected43 match 1 of 9 pixels differ1: upng-head	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	≠	✓	✓	✓
y_adam7-2x7-ga8png IHDRIDATIEND 2x7, interlaced, random filter per scanline; passes 2, 4 are empty. §8.1 says decoders are required to read interlaced images. §9.1 says an empty pass has no filter type bytes. expected: display, conforms spec: §13.10 expected40 match 4 of 14 pixels differ2: imagesharp, imagesharp-head 3 of 14 pixels differ1: upng-head 1 of 14 pixels differ1: upng	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	≠	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	≠	≠	✓	✓	✓
y_adam7-7x2-ga8png IHDRIDATIEND 7x2, interlaced, random filter per scanline; passes 3, 5 are empty. §8.1 says decoders are required to read interlaced images. §9.1 says an empty pass has no filter type bytes. expected: display, conforms spec: §13.10 expected43 match 2 of 14 pixels differ1: upng-head	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	≠	✓	✓	✓
y_adam7-8x9-ga8png IHDRIDATIEND 8x9, interlaced, random filter per scanline; no pass is empty. §8.1 says decoders are required to read interlaced images. expected: display, conforms spec: §13.10 expected43 match 1 of 72 pixels differ1: upng-head	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	≠	✓	✓	✓
y_adam7-ga16png IHDRIDATIEND 13x15, interlaced, random filter per scanline; no pass is empty. §8.1 says decoders are required to read interlaced images. expected: display, conforms spec: §13.10 expected38 match matches the reference; color under alpha 0 preserved; 16→8 high byte6: upng, pillow, chunky_png, upng-head, pillow-head, chunky_png-head	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓
y_adam7-1x1-ga16png IHDRIDATIEND 1x1, interlaced, random filter per scanline; passes 2, 3, 4, 5, 6, 7 are empty. §8.1 says decoders are required to read interlaced images. §9.1 says an empty pass has no filter type bytes. §9.1 says an empty pass has no filter type bytes. expected: display, conforms spec: §13.10 expected38 match matches the reference; 16→8 high byte6: upng, pillow, chunky_png, upng-head, pillow-head, chunky_png-head	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓
y_adam7-1x2-ga16png IHDRIDATIEND 1x2, interlaced, random filter per scanline; passes 2, 3, 4, 5, 6 are empty. §8.1 says decoders are required to read interlaced images. §9.1 says an empty pass has no filter type bytes. §9.1 says an empty pass has no filter type bytes. expected: display, conforms spec: §13.10 expected36 match matches the reference; 16→8 high byte5: pillow, chunky_png, upng-head, pillow-head, chunky_png-head 2 of 2 pixels differ2: imagesharp, imagesharp-head 2 of 2 pixels differ1: upng	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	≠	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	≠	✓	✓	✓	✓
y_adam7-2x1-ga16png IHDRIDATIEND 2x1, interlaced, random filter per scanline; passes 2, 3, 4, 5, 7 are empty. §8.1 says decoders are required to read interlaced images. §9.1 says an empty pass has no filter type bytes. §9.1 says an empty pass has no filter type bytes. expected: display, conforms spec: §13.10 expected36 match matches the reference; 16→8 high byte4: pillow, chunky_png, pillow-head, chunky_png-head 1 of 2 pixels differ2: imagesharp, imagesharp-head 2 of 2 pixels differ1: upng 2 of 2 pixels differ1: upng-head	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	≠	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	≠	≠	✓	✓	✓
y_adam7-2x2-ga16png IHDRIDATIEND 2x2, interlaced, random filter per scanline; passes 2, 3, 4, 5 are empty. §8.1 says decoders are required to read interlaced images. §9.1 says an empty pass has no filter type bytes. §9.1 says an empty pass has no filter type bytes. expected: display, conforms spec: §13.10 expected36 match matches the reference; 16→8 high byte5: pillow, chunky_png, upng-head, pillow-head, chunky_png-head 4 of 4 pixels differ2: imagesharp, imagesharp-head 4 of 4 pixels differ1: upng	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	≠	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	≠	✓	✓	✓	✓
y_adam7-3x3-ga16png IHDRIDATIEND 3x3, interlaced, random filter per scanline; passes 2, 3 are empty. §8.1 says decoders are required to read interlaced images. §9.1 says an empty pass has no filter type bytes. §9.1 says an empty pass has no filter type bytes. expected: display, conforms spec: §13.10 expected36 match matches the reference; 16→8 high byte4: pillow, chunky_png, pillow-head, chunky_png-head 9 of 9 pixels differ2: upng, upng-head	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	R	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	≠	≠	✓	✓	✓
y_adam7-4x4-ga16png IHDRIDATIEND 4x4, interlaced, random filter per scanline; passes 2, 3 are empty. §8.1 says decoders are required to read interlaced images. §9.1 says an empty pass has no filter type bytes. §9.1 says an empty pass has no filter type bytes. expected: display, conforms spec: §13.10 expected36 match matches the reference; 16→8 high byte5: upng, pillow, chunky_png, pillow-head, chunky_png-head 16 of 16 pixels differ1: upng-head	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	R	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	≠	✓	✓	✓
y_adam7-5x5-ga16png IHDRIDATIEND 5x5, interlaced, random filter per scanline; no pass is empty. §8.1 says decoders are required to read interlaced images. expected: display, conforms spec: §13.10 expected38 match matches the reference; 16→8 high byte6: upng, pillow, chunky_png, upng-head, pillow-head, chunky_png-head	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓
y_adam7-1x9-ga16png IHDRIDATIEND 1x9, interlaced, random filter per scanline; passes 2, 4, 6 are empty. §8.1 says decoders are required to read interlaced images. §9.1 says an empty pass has no filter type bytes. expected: display, conforms spec: §13.10 expected36 match matches the reference; 16→8 high byte4: pillow, chunky_png, pillow-head, chunky_png-head 9 of 9 pixels differ2: imagesharp, imagesharp-head 9 of 9 pixels differ1: upng-head 9 of 9 pixels differ1: upng	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	≠	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	≠	≠	✓	✓	✓
y_adam7-9x1-ga16png IHDRIDATIEND 9x1, interlaced, random filter per scanline; passes 3, 5, 7 are empty. §8.1 says decoders are required to read interlaced images. §9.1 says an empty pass has no filter type bytes. expected: display, conforms spec: §13.10 expected38 match matches the reference; 16→8 high byte5: upng, pillow, chunky_png, pillow-head, chunky_png-head 9 of 9 pixels differ1: upng-head	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	≠	✓	✓	✓
y_adam7-2x7-ga16png IHDRIDATIEND 2x7, interlaced, random filter per scanline; passes 2, 4 are empty. §8.1 says decoders are required to read interlaced images. §9.1 says an empty pass has no filter type bytes. expected: display, conforms spec: §13.10 expected36 match matches the reference; 16→8 high byte4: pillow, chunky_png, pillow-head, chunky_png-head 4 of 14 pixels differ2: imagesharp, imagesharp-head 14 of 14 pixels differ1: upng 14 of 14 pixels differ1: upng-head	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	≠	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	≠	≠	✓	✓	✓
y_adam7-7x2-ga16png IHDRIDATIEND 7x2, interlaced, random filter per scanline; passes 3, 5 are empty. §8.1 says decoders are required to read interlaced images. §9.1 says an empty pass has no filter type bytes. expected: display, conforms spec: §13.10 expected38 match matches the reference; 16→8 high byte5: upng, pillow, chunky_png, pillow-head, chunky_png-head 14 of 14 pixels differ1: upng-head	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	≠	✓	✓	✓
y_adam7-8x9-ga16png IHDRIDATIEND 8x9, interlaced, random filter per scanline; no pass is empty. §8.1 says decoders are required to read interlaced images. expected: display, conforms spec: §13.10 expected38 match matches the reference; 16→8 high byte5: upng, pillow, chunky_png, pillow-head, chunky_png-head 71 of 72 pixels differ1: upng-head	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	≠	✓	✓	✓
y_adam7-rgba8png IHDRIDATIEND 13x15, interlaced, random filter per scanline; no pass is empty. §8.1 says decoders are required to read interlaced images. expected: display, conforms spec: §13.10 expected43 match 36 of 195 pixels differ1: upng-head	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	≠	✓	✓	✓
y_adam7-1x1-rgba8png IHDRIDATIEND 1x1, interlaced, random filter per scanline; passes 2, 3, 4, 5, 6, 7 are empty. §8.1 says decoders are required to read interlaced images. §9.1 says an empty pass has no filter type bytes. §9.1 says an empty pass has no filter type bytes. expected: display, conforms spec: §13.10 expected44 match	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓
y_adam7-1x2-rgba8png IHDRIDATIEND 1x2, interlaced, random filter per scanline; passes 2, 3, 4, 5, 6 are empty. §8.1 says decoders are required to read interlaced images. §9.1 says an empty pass has no filter type bytes. §9.1 says an empty pass has no filter type bytes. expected: display, conforms spec: §13.10 expected41 match 2 of 2 pixels differ2: imagesharp, imagesharp-head 1 of 2 pixels differ1: upng	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	≠	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	≠	✓	✓	✓	✓
y_adam7-2x1-rgba8png IHDRIDATIEND 2x1, interlaced, random filter per scanline; passes 2, 3, 4, 5, 7 are empty. §8.1 says decoders are required to read interlaced images. §9.1 says an empty pass has no filter type bytes. §9.1 says an empty pass has no filter type bytes. expected: display, conforms spec: §13.10 expected42 match 1 of 2 pixels differ2: imagesharp, imagesharp-head	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	≠	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓
y_adam7-2x2-rgba8png IHDRIDATIEND 2x2, interlaced, random filter per scanline; passes 2, 3, 4, 5 are empty. §8.1 says decoders are required to read interlaced images. §9.1 says an empty pass has no filter type bytes. §9.1 says an empty pass has no filter type bytes. expected: display, conforms spec: §13.10 expected41 match 4 of 4 pixels differ2: imagesharp, imagesharp-head 1 of 4 pixels differ1: upng	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	≠	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	≠	✓	✓	✓	✓
y_adam7-3x3-rgba8png IHDRIDATIEND 3x3, interlaced, random filter per scanline; passes 2, 3 are empty. §8.1 says decoders are required to read interlaced images. §9.1 says an empty pass has no filter type bytes. §9.1 says an empty pass has no filter type bytes. expected: display, conforms spec: §13.10 expected41 match 2 of 9 pixels differ1: upng-head	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	R	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	≠	✓	✓	✓
y_adam7-4x4-rgba8png IHDRIDATIEND 4x4, interlaced, random filter per scanline; passes 2, 3 are empty. §8.1 says decoders are required to read interlaced images. §9.1 says an empty pass has no filter type bytes. §9.1 says an empty pass has no filter type bytes. expected: display, conforms spec: §13.10 expected40 match 1 of 16 pixels differ2: upng, upng-head	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	R	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	≠	≠	✓	✓	✓
y_adam7-5x5-rgba8png IHDRIDATIEND 5x5, interlaced, random filter per scanline; no pass is empty. §8.1 says decoders are required to read interlaced images. expected: display, conforms spec: §13.10 expected43 match 1 of 25 pixels differ1: upng-head	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	≠	✓	✓	✓
y_adam7-1x9-rgba8png IHDRIDATIEND 1x9, interlaced, random filter per scanline; passes 2, 4, 6 are empty. §8.1 says decoders are required to read interlaced images. §9.1 says an empty pass has no filter type bytes. expected: display, conforms spec: §13.10 expected40 match 9 of 9 pixels differ2: imagesharp, imagesharp-head 6 of 9 pixels differ1: upng-head 1 of 9 pixels differ1: upng	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	≠	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	≠	≠	✓	✓	✓
y_adam7-9x1-rgba8png IHDRIDATIEND 9x1, interlaced, random filter per scanline; passes 3, 5, 7 are empty. §8.1 says decoders are required to read interlaced images. §9.1 says an empty pass has no filter type bytes. expected: display, conforms spec: §13.10 expected43 match 2 of 9 pixels differ1: upng-head	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	≠	✓	✓	✓
y_adam7-2x7-rgba8png IHDRIDATIEND 2x7, interlaced, random filter per scanline; passes 2, 4 are empty. §8.1 says decoders are required to read interlaced images. §9.1 says an empty pass has no filter type bytes. expected: display, conforms spec: §13.10 expected40 match 4 of 14 pixels differ2: imagesharp, imagesharp-head 1 of 14 pixels differ1: upng 6 of 14 pixels differ1: upng-head	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	≠	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	≠	≠	✓	✓	✓
y_adam7-7x2-rgba8png IHDRIDATIEND 7x2, interlaced, random filter per scanline; passes 3, 5 are empty. §8.1 says decoders are required to read interlaced images. §9.1 says an empty pass has no filter type bytes. expected: display, conforms spec: §13.10 expected43 match 1 of 14 pixels differ1: upng-head	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	≠	✓	✓	✓
y_adam7-8x9-rgba8png IHDRIDATIEND 8x9, interlaced, random filter per scanline; no pass is empty. §8.1 says decoders are required to read interlaced images. expected: display, conforms spec: §13.10 expected43 match 1 of 72 pixels differ1: upng-head	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	≠	✓	✓	✓
y_adam7-rgba16png IHDRIDATIEND 13x15, interlaced, random filter per scanline; no pass is empty. §8.1 says decoders are required to read interlaced images. expected: display, conforms spec: §13.10 expected38 match matches the reference; color under alpha 0 preserved; 16→8 high byte5: upng, pillow, chunky_png, pillow-head, chunky_png-head 192 of 195 pixels differ1: upng-head	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	≠	✓	✓	✓
y_adam7-1x1-rgba16png IHDRIDATIEND 1x1, interlaced, random filter per scanline; passes 2, 3, 4, 5, 6, 7 are empty. §8.1 says decoders are required to read interlaced images. §9.1 says an empty pass has no filter type bytes. §9.1 says an empty pass has no filter type bytes. expected: display, conforms spec: §13.10 expected38 match matches the reference; 16→8 high byte6: upng, pillow, chunky_png, upng-head, pillow-head, chunky_png-head	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓
y_adam7-1x2-rgba16png IHDRIDATIEND 1x2, interlaced, random filter per scanline; passes 2, 3, 4, 5, 6 are empty. §8.1 says decoders are required to read interlaced images. §9.1 says an empty pass has no filter type bytes. §9.1 says an empty pass has no filter type bytes. expected: display, conforms spec: §13.10 expected36 match matches the reference; 16→8 high byte5: pillow, chunky_png, upng-head, pillow-head, chunky_png-head 2 of 2 pixels differ2: imagesharp, imagesharp-head 2 of 2 pixels differ1: upng	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	≠	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	≠	✓	✓	✓	✓
y_adam7-2x1-rgba16png IHDRIDATIEND 2x1, interlaced, random filter per scanline; passes 2, 3, 4, 5, 7 are empty. §8.1 says decoders are required to read interlaced images. §9.1 says an empty pass has no filter type bytes. §9.1 says an empty pass has no filter type bytes. expected: display, conforms spec: §13.10 expected36 match matches the reference; 16→8 high byte4: pillow, chunky_png, pillow-head, chunky_png-head 1 of 2 pixels differ2: imagesharp, imagesharp-head 2 of 2 pixels differ1: upng-head 2 of 2 pixels differ1: upng	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	≠	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	≠	≠	✓	✓	✓
y_adam7-2x2-rgba16png IHDRIDATIEND 2x2, interlaced, random filter per scanline; passes 2, 3, 4, 5 are empty. §8.1 says decoders are required to read interlaced images. §9.1 says an empty pass has no filter type bytes. §9.1 says an empty pass has no filter type bytes. expected: display, conforms spec: §13.10 expected36 match matches the reference; 16→8 high byte4: pillow, chunky_png, pillow-head, chunky_png-head 4 of 4 pixels differ2: imagesharp, imagesharp-head 4 of 4 pixels differ1: upng-head 4 of 4 pixels differ1: upng	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	≠	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	≠	≠	✓	✓	✓
y_adam7-3x3-rgba16png IHDRIDATIEND 3x3, interlaced, random filter per scanline; passes 2, 3 are empty. §8.1 says decoders are required to read interlaced images. §9.1 says an empty pass has no filter type bytes. §9.1 says an empty pass has no filter type bytes. expected: display, conforms spec: §13.10 expected36 match matches the reference; 16→8 high byte5: pillow, chunky_png, upng-head, pillow-head, chunky_png-head 9 of 9 pixels differ1: upng	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	R	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	≠	✓	✓	✓	✓
y_adam7-4x4-rgba16png IHDRIDATIEND 4x4, interlaced, random filter per scanline; passes 2, 3 are empty. §8.1 says decoders are required to read interlaced images. §9.1 says an empty pass has no filter type bytes. §9.1 says an empty pass has no filter type bytes. expected: display, conforms spec: §13.10 expected36 match matches the reference; 16→8 high byte5: pillow, chunky_png, upng-head, pillow-head, chunky_png-head 16 of 16 pixels differ1: upng	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	R	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	≠	✓	✓	✓	✓
y_adam7-5x5-rgba16png IHDRIDATIEND 5x5, interlaced, random filter per scanline; no pass is empty. §8.1 says decoders are required to read interlaced images. expected: display, conforms spec: §13.10 expected38 match matches the reference; 16→8 high byte5: upng, pillow, chunky_png, pillow-head, chunky_png-head 24 of 25 pixels differ1: upng-head	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	≠	✓	✓	✓
y_adam7-1x9-rgba16png IHDRIDATIEND 1x9, interlaced, random filter per scanline; passes 2, 4, 6 are empty. §8.1 says decoders are required to read interlaced images. §9.1 says an empty pass has no filter type bytes. expected: display, conforms spec: §13.10 expected36 match matches the reference; 16→8 high byte4: pillow, chunky_png, pillow-head, chunky_png-head 9 of 9 pixels differ2: imagesharp, imagesharp-head 9 of 9 pixels differ1: upng 9 of 9 pixels differ1: upng-head	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	≠	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	≠	≠	✓	✓	✓
y_adam7-9x1-rgba16png IHDRIDATIEND 9x1, interlaced, random filter per scanline; passes 3, 5, 7 are empty. §8.1 says decoders are required to read interlaced images. §9.1 says an empty pass has no filter type bytes. expected: display, conforms spec: §13.10 expected38 match matches the reference; 16→8 high byte5: upng, pillow, chunky_png, pillow-head, chunky_png-head 9 of 9 pixels differ1: upng-head	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	≠	✓	✓	✓
y_adam7-2x7-rgba16png IHDRIDATIEND 2x7, interlaced, random filter per scanline; passes 2, 4 are empty. §8.1 says decoders are required to read interlaced images. §9.1 says an empty pass has no filter type bytes. expected: display, conforms spec: §13.10 expected36 match matches the reference; 16→8 high byte4: pillow, chunky_png, pillow-head, chunky_png-head 4 of 14 pixels differ2: imagesharp, imagesharp-head 14 of 14 pixels differ1: upng-head 14 of 14 pixels differ1: upng	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	≠	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	≠	≠	✓	✓	✓
y_adam7-7x2-rgba16png IHDRIDATIEND 7x2, interlaced, random filter per scanline; passes 3, 5 are empty. §8.1 says decoders are required to read interlaced images. §9.1 says an empty pass has no filter type bytes. expected: display, conforms spec: §13.10 expected38 match matches the reference; 16→8 high byte5: upng, pillow, chunky_png, pillow-head, chunky_png-head 14 of 14 pixels differ1: upng-head	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	≠	✓	✓	✓
y_adam7-8x9-rgba16png IHDRIDATIEND 8x9, interlaced, random filter per scanline; no pass is empty. §8.1 says decoders are required to read interlaced images. expected: display, conforms spec: §13.10 expected38 match matches the reference; 16→8 high byte5: upng, pillow, chunky_png, pillow-head, chunky_png-head 72 of 72 pixels differ1: upng-head	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	≠	✓	✓	✓
y_adam7-g8-nofilterpng IHDRIDATIEND 13x15, interlaced, filter None throughout; no pass is empty. §8.1 says decoders are required to read interlaced images. expected: display, conforms spec: §13.10 expected44 match	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓
y_adam7-1x1-g8-nofilterpng IHDRIDATIEND 1x1, interlaced, filter None throughout; passes 2, 3, 4, 5, 6, 7 are empty. §8.1 says decoders are required to read interlaced images. §9.1 says an empty pass has no filter type bytes. §9.1 says an empty pass has no filter type bytes. expected: display, conforms spec: §13.10 expected44 match	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓
y_adam7-1x2-g8-nofilterpng IHDRIDATIEND 1x2, interlaced, filter None throughout; passes 2, 3, 4, 5, 6 are empty. §8.1 says decoders are required to read interlaced images. §9.1 says an empty pass has no filter type bytes. §9.1 says an empty pass has no filter type bytes. expected: display, conforms spec: §13.10 expected42 match 2 of 2 pixels differ2: imagesharp, imagesharp-head	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	≠	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓
y_adam7-2x1-g8-nofilterpng IHDRIDATIEND 2x1, interlaced, filter None throughout; passes 2, 3, 4, 5, 7 are empty. §8.1 says decoders are required to read interlaced images. §9.1 says an empty pass has no filter type bytes. §9.1 says an empty pass has no filter type bytes. expected: display, conforms spec: §13.10 expected42 match 1 of 2 pixels differ2: imagesharp, imagesharp-head	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	≠	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓
y_adam7-2x2-g8-nofilterpng IHDRIDATIEND 2x2, interlaced, filter None throughout; passes 2, 3, 4, 5 are empty. §8.1 says decoders are required to read interlaced images. §9.1 says an empty pass has no filter type bytes. §9.1 says an empty pass has no filter type bytes. expected: display, conforms spec: §13.10 expected42 match 4 of 4 pixels differ2: imagesharp, imagesharp-head	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	≠	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓
y_adam7-3x3-g8-nofilterpng IHDRIDATIEND 3x3, interlaced, filter None throughout; passes 2, 3 are empty. §8.1 says decoders are required to read interlaced images. §9.1 says an empty pass has no filter type bytes. §9.1 says an empty pass has no filter type bytes. expected: display, conforms spec: §13.10 expected42 match	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	R	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓
y_adam7-4x4-g8-nofilterpng IHDRIDATIEND 4x4, interlaced, filter None throughout; passes 2, 3 are empty. §8.1 says decoders are required to read interlaced images. §9.1 says an empty pass has no filter type bytes. §9.1 says an empty pass has no filter type bytes. expected: display, conforms spec: §13.10 expected42 match	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	R	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓
y_adam7-5x5-g8-nofilterpng IHDRIDATIEND 5x5, interlaced, filter None throughout; no pass is empty. §8.1 says decoders are required to read interlaced images. expected: display, conforms spec: §13.10 expected43 match 1 of 25 pixels differ1: upng-head	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	≠	✓	✓	✓
y_adam7-1x9-g8-nofilterpng IHDRIDATIEND 1x9, interlaced, filter None throughout; passes 2, 4, 6 are empty. §8.1 says decoders are required to read interlaced images. §9.1 says an empty pass has no filter type bytes. expected: display, conforms spec: §13.10 expected42 match 9 of 9 pixels differ2: imagesharp, imagesharp-head	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	≠	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓
y_adam7-9x1-g8-nofilterpng IHDRIDATIEND 9x1, interlaced, filter None throughout; passes 3, 5, 7 are empty. §8.1 says decoders are required to read interlaced images. §9.1 says an empty pass has no filter type bytes. expected: display, conforms spec: §13.10 expected43 match 2 of 9 pixels differ1: upng-head	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	≠	✓	✓	✓
y_adam7-2x7-g8-nofilterpng IHDRIDATIEND 2x7, interlaced, filter None throughout; passes 2, 4 are empty. §8.1 says decoders are required to read interlaced images. §9.1 says an empty pass has no filter type bytes. expected: display, conforms spec: §13.10 expected42 match 4 of 14 pixels differ2: imagesharp, imagesharp-head	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	≠	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓
y_adam7-7x2-g8-nofilterpng IHDRIDATIEND 7x2, interlaced, filter None throughout; passes 3, 5 are empty. §8.1 says decoders are required to read interlaced images. §9.1 says an empty pass has no filter type bytes. expected: display, conforms spec: §13.10 expected43 match 1 of 14 pixels differ1: upng-head	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	≠	✓	✓	✓
y_adam7-8x9-g8-nofilterpng IHDRIDATIEND 8x9, interlaced, filter None throughout; no pass is empty. §8.1 says decoders are required to read interlaced images. expected: display, conforms spec: §13.10 expected43 match 1 of 72 pixels differ1: upng-head	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	≠	✓	✓	✓
y_padbits-g1png IHDRIDATIEND the 3 unused bits at the end of every scanline set to 1; Sub filter, so they feed the filter. §7.2 says the padding bits at the end of a scanline are unspecified; a decoder can't depend on them. expected: display, conforms expected43 match 100 of 195 pixels differ1: upng	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	≠	✓	✓	✓	✓
y_padbits-g2png IHDRIDATIEND the 6 unused bits at the end of every scanline set to 1; Sub filter, so they feed the filter. §7.2 says the padding bits at the end of a scanline are unspecified; a decoder can't depend on them. expected: display, conforms expected43 match 118 of 195 pixels differ1: upng	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	≠	✓	✓	✓	✓
y_padbits-g4png IHDRIDATIEND the 4 unused bits at the end of every scanline set to 1; Sub filter, so they feed the filter. §7.2 says the padding bits at the end of a scanline are unspecified; a decoder can't depend on them. expected: display, conforms expected43 match 122 of 195 pixels differ1: upng	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	≠	✓	✓	✓	✓
y_padbits-p1png IHDRPLTEIDATIEND the 3 unused bits at the end of every scanline set to 1; Sub filter, so they feed the filter. §7.2 says the padding bits at the end of a scanline are unspecified; a decoder can't depend on them. expected: display, conforms expected44 match	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓
y_padbits-p2png IHDRPLTEIDATIEND the 6 unused bits at the end of every scanline set to 1; Sub filter, so they feed the filter. §7.2 says the padding bits at the end of a scanline are unspecified; a decoder can't depend on them. expected: display, conforms expected44 match	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓
y_padbits-p4png IHDRPLTEIDATIEND the 4 unused bits at the end of every scanline set to 1; Sub filter, so they feed the filter. §7.2 says the padding bits at the end of a scanline are unspecified; a decoder can't depend on them. expected: display, conforms expected44 match	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓
y_padbits-g1-adam7png IHDRIDATIEND unused bits set to 1 in every reduced image (13 wide, so every pass pads), Paeth filter. §8.1 says decoders are required to read interlaced images. §7.2 says the padding bits at the end of a scanline are unspecified; a decoder can't depend on them. expected: display, conforms spec: §13.10 expected40 match 89 of 195 pixels differ1: upng 12 of 195 pixels differ1: upng-head	✓	✓	✓	✓	✓	R	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	≠	≠	✓	✓	✓
y_idat-empty-firstpng IHDRIDAT ×2IEND zero-length IDAT before the data. §10.2 says an IDAT may be empty. expected: display, conforms spec: §11.2.3 expected42 match	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	R	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓
y_idat-empty-lastpng IHDRIDAT ×2IEND zero-length IDAT after the data. §10.2 says an IDAT may be empty. expected: display, conforms spec: §11.2.3 expected44 match	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓
y_idat-empty-middlepng IHDRIDAT ×3IEND zero-length IDAT between two halves. §10.2 says an IDAT may be empty. expected: display, conforms spec: §11.2.3 expected44 match	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓
y_idat-split-every-bytepng IHDRIDAT ×188IEND one byte per IDAT, 188 IDAT chunks. §10.2 says IDAT boundaries mean nothing; the chunks' data concatenate into one stream. expected: display, conforms spec: §13.8 expected42 match	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	R	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓
y_idat-split-every-byte-g16png IHDRIDAT ×158IEND one byte per IDAT on a 16-bit image, 158 IDAT chunks. §10.2 says IDAT boundaries mean nothing; the chunks' data concatenate into one stream. expected: display, conforms spec: §13.8 expected38 match matches the reference; 16→8 high byte4: upng, chunky_png, upng-head, chunky_png-head	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	R	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓
y_idat-split-every-byte-rgb16png IHDRIDAT ×301IEND one byte per IDAT on a 16-bit image, 301 IDAT chunks. §10.2 says IDAT boundaries mean nothing; the chunks' data concatenate into one stream. expected: display, conforms spec: §13.8 expected36 match matches the reference; 16→8 high byte6: upng, pillow, chunky_png, upng-head, pillow-head, chunky_png-head	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	R	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓
y_idat-split-in-zlib-headerpng IHDRIDAT ×2IEND IDAT boundary between the two zlib header bytes. §10.2 says IDAT boundaries can fall anywhere, even inside the zlib header. expected: display, conforms spec: §13.8 expected42 match	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	R	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓
y_idat-split-in-adlerpng IHDRIDAT ×2IEND IDAT boundary inside the Adler-32. §10.2 says IDAT boundaries can fall anywhere, even inside the Adler-32. expected: display, conforms spec: §13.8 expected44 match	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓
n_idat-interrupted-by-textpng IHDRIDATtEXtIDATIEND tEXt between two IDATs. §11.2.3 says IDAT chunks are consecutive, so that's a fatal error. expected: must-reject, does not conform spec: §5.6 expected17 match 193 of 195 pixels differ2: imagesharp, imagesharp-head	R	R	R	R	A	A	A	A	R	R	R	R	R	A	R	R	R	R	A	R	R	R	R	A	A	R	R	A	A	R	R	A	A	A	R	A	R
n_idat-interrupted-by-unknownpng IHDRIDATjuNkIDATIEND unknown ancillary chunk between two IDATs. §11.2.3 says IDAT chunks are consecutive, so that's a fatal error. expected: must-reject, does not conform spec: §5.6 expected17 match 193 of 195 pixels differ2: imagesharp, imagesharp-head	R	R	R	R	A	A	A	A	R	R	R	R	R	A	R	R	R	R	A	R	R	R	R	A	A	R	R	A	A	R	R	A	A	A	R	A	R
r_idat-after-iendpng IHDRIDATIENDIDAT a complete image, then a second IDAT after IEND. §11.2.4 says IEND is the last chunk, therefore a decoder may ignore anything past it. expected: recover, does not conform spec: §15.3.1, §13.1, §13.3 expected42 match	✓	✓	R	R	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	R	R	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓
r_idat-second-streampng IHDRIDAT ×2IEND a second complete zlib stream in a further IDAT. §11.2.3 says a decoder should ignore unused bytes after the compressed data. expected: recover, does not conform expected42 match	✓	✓	A	A	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	R	R	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓
r_idat-trailing-junkpng IHDRIDATIEND 16 unused bytes after the zlib stream in the final IDAT. §11.2.3 says a decoder should ignore unused bytes after the compressed data. expected: recover, does not conform expected38 match	✓	✓	A	A	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	R	✓	✓	✓	✓	R	R	✓	✓	✓	✓	✓	✓	✓	✓	✓	R	✓	✓
r_idat-trailing-zerospng IHDRIDATIEND 64 zero bytes after the zlib stream. §11.2.3 says a decoder should ignore unused bytes after the compressed data. expected: recover, does not conform expected38 match	✓	✓	A	A	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	R	✓	✓	✓	✓	R	R	✓	✓	✓	✓	✓	✓	✓	✓	✓	R	✓	✓
i_zlib-extra-rowpng IHDRIDATIEND decompressed data one scanline longer than the image. The spec doesn't address extra data after the last scanline; a decoder may reject it or ignore it. expected: may-reject, does not conform spec: §11.2.3, §13.1 expected33 match	✓	✓	A	A	✓	✓	✓	✓	R	✓	✓	✓	✓	✓	✓	✓	✓	✓	R	✓	✓	✓	✓	R	R	✓	✓	!	!	✓	✓	✓	✓	✓	R	✓	R
i_zlib-extra-bytepng IHDRIDATIEND decompressed data one byte longer than the image. The spec doesn't address extra data after the last scanline; a decoder may reject it or ignore it. expected: may-reject, does not conform spec: §11.2.3, §13.1 expected33 match	✓	✓	A	A	✓	✓	✓	✓	R	✓	✓	✓	✓	✓	✓	✓	✓	✓	R	✓	✓	✓	✓	R	R	✓	✓	R	R	✓	✓	✓	✓	✓	R	✓	R
i_zlib-short-rowpng IHDRIDATIEND decompressed data one scanline short: unexpected end of image data. §13.1 says a decoder may treat an early end of the image data as fatal. The image is incomplete, so what a decoder shows for it isn't judged. expected: may-reject, does not conform no reference pixels8: ffmpeg, imagesharp, pillow, ffmpeg-head, zune-png-head, imagesharp-head, upng-head, pillow-head no reference pixels1: upng	R	R	A	A	R	R	A	A	R	R	R	R	R	A	R	R	R	R	R	R	R	A	A	R	R	R	R	!	!	R	R	R	A	A	R	R	A
i_zlib-short-bytepng IHDRIDATIEND decompressed data one byte short. §13.1 says a decoder may treat an early end of the image data as fatal. The image is incomplete, so what a decoder shows for it isn't judged. expected: may-reject, does not conform no reference pixels6: fast-png, pngjs, upng, fast-png-head, pngjs-head, upng-head no reference pixels5: ffmpeg, imagesharp, ffmpeg-head, zune-png-head, imagesharp-head	R	R	A	A	!	A	A	A	R	R	R	R	R	A	R	R	R	R	R	R	R	R	R	A	A	R	R	R	R	R	R	R	A	A	R	R	A
i_zlib-emptypng IHDRIDATIEND a valid zlib stream that decompresses to nothing. §13.1 says a decoder may treat an early end of the image data as fatal. The image is incomplete, so what a decoder shows for it isn't judged. expected: may-reject, does not conform no reference pixels5: imagesharp, upng, zune-png-head, imagesharp-head, upng-head	R	R	R	R	R	R	R	R	R	R	R	R	R	A	R	R	R	R	R	R	R	R	R	R	R	R	R	!	!	R	R	R	A	A	R	R	A
i_zlib-no-adlerpng IHDRIDATIEND deflate complete, Adler-32 absent. §10.1 says the stream ends with its Adler-32, but not what a decoder does when the stream stops early; a decoder may reject the file or keep the image. RFC 1950 §2.2 ends the stream with four Adler-32 bytes; a decoder may treat a cut checksum as fatal or keep the image. expected: may-reject, does not conform expected22 match	✓	✓	A	A	R	R	✓	✓	R	R	R	R	R	✓	✓	R	R	✓	R	R	R	✓	✓	✓	✓	R	R	✓	✓	✓	✓	✓	R	✓	R	✓	✓
i_idat-second-truncatedpng IHDRIDATIDAT a complete IDAT, then the length and type of a second one and nothing more: the image is whole, the datastream is not. §13.1 says a datastream that ends mid-chunk is corrupt, and a decoder may treat that as fatal. expected: may-reject, does not conform expected8 match 193 of 195 pixels differ1: zune-png-head	✓	✓	R	R	R	R	R	R	R	R	R	R	R	R	✓	R	R	✓	R	R	R	R	R	R	R	R	R	R	R	R	R	R	R	✓	✓	R	≠
n_zlib-bad-adler-idatpng IHDRIDATIEND Adler-32 wrong, in the IDAT that holds the data: a decoder that inflates the chunk it has in hand reaches it. RFC 1950 §2.3 says a decompressor must check the Adler-32 and report an error when it's wrong. expected: must-reject, does not conform spec: RFC 1950 §2.2 expected15 match	R	R	R	R	R	A	R	R	R	R	R	R	R	A	R	R	R	R	R	R	R	R	R	A	A	R	R	R	R	A	A	A	R	A	A	A	A
n_zlib-bad-adler-extra-idatpng IHDRIDAT ×2IEND Adler-32 wrong, in an extra IDAT after the data: a decoder that has every row before it reads the chunk may never check it. RFC 1950 §2.3 says a decompressor must check the Adler-32 and report an error when it's wrong. expected: must-reject, does not conform spec: RFC 1950 §2.2 expectedevery row comes before the checksum, and a decoder that stops at the last row never checks it; libpng checks it and treats the mismatch as benign31 match	R	R	A	A	R	A	R	R	R	A	A	A	A	A	A	A	A	A	R	A	A	A	A	A	A	A	A	R	R	A	A	A	R	A	A	A	A
i_zlib-no-final-blockpng IHDRIDATIEND all data in non-final blocks, then the stream stops (no BFINAL, no Adler-32). §10.1 says the stream ends with its Adler-32, but not what a decoder does when the stream stops early; a decoder may reject the file or keep the image. RFC 1951 §3.2.3 says blocks follow until a final one ends; input that stops first is an error a decoder may ignore once it has every row. expected: may-reject, does not conform spec: RFC 1950 §2.2, RFC 1951 §1.4 expected17 match	✓	✓	A	A	R	R	✓	✓	R	R	R	R	R	✓	✓	R	R	✓	R	R	R	✓	✓	✓	✓	R	R	✓	✓	✓	✓	R	R	R	R	R	R
n_zlib-cinfo-8png IHDRIDATIEND zlib header claims a 64 KiB window (CINFO 8); PNG allows at most 32768. §10.1 says the zlib header must specify method 8 and a window of at most 32768 bytes, so that's a fatal error. expected: must-reject, does not conform no reference pixels4: stb_image, stb_image-head, zune-png-head, upng-head	R	R	R	R	R	R	R	R	R	R	R	R	R	R	R	R	R	R	R	R	R	R	R	R	R	R	R	R	R	R	R	A	R	A	R	R	A
y_zlib-cinfo-0png IHDRIDATIEND zlib header claims a 256-byte window; the data uses no distance at all. RFC 1950 §2.2 says CINFO declares the window size; a smaller window is fine. expected: display, conforms expected42 match	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	R	✓	✓
n_zlib-fdictpng IHDRIDATIEND FDICT set with dictionary id 0x12345678; PNG forbids preset dictionaries; the data needs none (an id of 1 would be the Adler-32 of an empty dictionary and some inflaters accept it). §10.1 says the zlib header must not request a preset dictionary, so that's a fatal error. expected: must-reject, does not conform no reference pixels2: imagesharp, imagesharp-head	R	R	R	R	R	R	R	R	R	R	R	R	R	A	R	R	R	R	R	R	R	R	R	R	R	R	R	R	R	R	R	R	R	R	R	R	R
n_zlib-cm-7png IHDRIDATIEND zlib CM 7 instead of 8. §10.1 says the zlib header must specify method 8 and a window of at most 32768 bytes, so that's a fatal error. expected: must-reject, does not conform no reference pixels2: zune-png-head, upng-head	R	R	R	R	R	R	R	R	R	R	R	R	R	R	R	R	R	R	R	R	R	R	R	R	R	R	R	R	R	R	R	R	R	A	R	R	A
n_zlib-fcheck-badpng IHDRIDATIEND zlib header check bits wrong (0x789D), data intact. RFC 1950 §2.2 says the header bytes, read as a 16-bit integer, are a multiple of 31, so that's a fatal error. expected: must-reject, does not conform spec: RFC 1950 §2.3 no reference pixels4: imagesharp, zune-png-head, imagesharp-head, upng-head	R	R	R	R	R	R	R	R	R	R	R	R	R	A	R	R	R	R	R	R	R	R	R	R	R	R	R	R	R	R	R	R	R	A	R	R	A
i_zlib-cinfo-0-long-distancepng IHDRIDATIEND rgb16; window declared 256 bytes (CINFO 0), and 67 bytes of the last scanline are matches 316 bytes back (the ground repeats). RFC 1950 §2.2 doesn't say what to do with a distance beyond the declared window; a decoder may reject it or not. expected: may-reject, does not conform expected27 match matches the reference; 16→8 high byte5: pillow, chunky_png, upng-head, pillow-head, chunky_png-head	✓	✓	A	A	✓	✓	✓	✓	✓	R	R	R	R	✓	✓	R	R	✓	✓	R	R	✓	✓	✓	✓	R	R	✓	✓	✓	✓	✓	R	✓	✓	✓	✓
y_deflate-storedpng IHDRIDATIEND zlib level 0: stored blocks. expected: display, conforms spec: RFC 1951 §3.2.4 expected44 match	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓
y_deflate-fixedpng IHDRIDATIEND single fixed-Huffman block with distance-1 matches. expected: display, conforms spec: RFC 1951 §3.2.6 expected44 match	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓
y_deflate-huffman-onlypng IHDRIDATIEND zlib Z_HUFFMAN_ONLY: dynamic blocks without matches. expected: display, conforms spec: RFC 1951 §3.2.7 expected44 match	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓
y_deflate-rlepng IHDRIDATIEND zlib Z_RLE: distance-1 matches only. RFC 1951 §3.2.3 says a back-reference may overlap the bytes it produces. expected: display, conforms expected44 match	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓
y_deflate-zlib-fixedpng IHDRIDATIEND zlib Z_FIXED: fixed-Huffman blocks with real matches. expected: display, conforms spec: RFC 1951 §3.2.6 expected44 match	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓
y_deflate-sync-flush-per-rowpng IHDRIDATIEND Z_SYNC_FLUSH after every scanline: empty stored blocks between, matches may reach across. expected: display, conforms spec: RFC 1951 §3.2.3 expected44 match	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓
y_deflate-full-flush-per-rowpng IHDRIDATIEND Z_FULL_FLUSH after every scanline: no match reaches across a flush. expected: display, conforms spec: RFC 1951 §3.2.3 expected44 match	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓
y_deflate-stored-small-blockspng IHDRIDATIEND 7-byte stored blocks, then an empty final stored block. expected: display, conforms spec: RFC 1951 §3.2.3 expected44 match	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓
y_deflate-empty-blocks-firstpng IHDRIDATIEND 20 empty stored blocks before the data. expected: display, conforms spec: RFC 1951 §3.2.3 expected42 match	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	R	✓	✓
y_deflate-dynamic-literalspng IHDRIDATIEND hand-written dynamic block, literals only, two unused distance codes (what zlib emits). expected: display, conforms spec: RFC 1951 §3.2.7 expected44 match	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓
y_deflate-dynamic-no-distance-codespng IHDRIDATIEND HDIST=1 with that code length 0: no distance codes at all, which RFC 1951 allows. RFC 1951 §3.2.7 says one zero-length distance code means the block doesn't use distance codes at all. expected: display, conforms expected42 match	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	R	✓	✓
y_deflate-dynamic-one-distance-codepng IHDRIDATIEND a single distance code of length 1 (incomplete tree), which RFC 1951 allows; Up filter, so the repeated ground rows give 4 distance-1 matches. RFC 1951 §3.2.7 says a single distance code takes one bit, not zero. expected: display, conforms expected44 match	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓
y_deflate-dynamic-hdist-32-unusedpng IHDRIDATIEND HDIST=32: distance codes 30 and 31 given lengths but never used. RFC 1951 §3.2.7 allows 1 to 32 distance codes, and RFC 1951 §3.3 says a decompressor must accept the full range. zlib refuses 31 and 32. expected: display, conforms expected11 match	✓	✓	R	R	R	✓	R	R	R	R	R	R	R	R	R	R	R	R	✓	R	R	R	R	R	R	R	R	R	R	R	R	✓	R	✓	R	✓	✓
y_deflate-dynamic-hdist-31-unusedpng IHDRIDATIEND HDIST=31: distance code 30 given a length (4, so the tree is complete) but never used. RFC 1951 §3.2.7 allows 1 to 32 distance codes, and RFC 1951 §3.3 says a decompressor must accept the full range. zlib refuses 31 and 32. expected: display, conforms expected11 match	✓	✓	R	R	R	✓	R	R	R	R	R	R	R	R	R	R	R	R	✓	R	R	R	R	R	R	R	R	R	R	R	R	✓	R	✓	R	✓	✓
n_deflate-stored-bad-nlenpng IHDRIDATIEND stored block whose NLEN is not the complement of LEN. RFC 1951 §3.2.4 says NLEN is the one's complement of LEN, so that's a fatal error. expected: must-reject, does not conform no reference pixels3: fast-png, fast-png-head, upng-head	R	R	R	R	R	A	R	R	R	R	R	R	R	R	R	R	R	R	R	R	R	R	R	R	R	R	R	R	R	R	R	R	R	A	R	R	R
n_deflate-distance-too-farpng IHDRIDATIEND a match reaching 5 bytes back after 1 byte of output. RFC 1951 §3.2.3 says a distance can't reach before the start of the output, so that's a fatal error. expected: must-reject, does not conform no reference pixels1: upng-head	R	R	R	R	R	R	R	R	R	R	R	R	R	R	R	R	R	R	R	R	R	R	R	R	R	R	R	R	R	R	R	R	R	A	R	R	R
n_deflate-fixed-length-code-286-usedpng IHDRIDATIEND fixed-Huffman block using literal/length code 286, which has no meaning. RFC 1951 §3.2.6 says symbols 286 and 287 never occur in data, so that's a fatal error. expected: must-reject, does not conform no reference pixels1: upng-head	R	R	R	R	R	R	R	R	R	R	R	R	R	R	R	R	R	R	R	R	R	R	R	R	R	R	R	R	R	R	R	R	R	A	R	R	R
n_deflate-fixed-distance-code-30-usedpng IHDRIDATIEND fixed-Huffman block using distance code 30, which has no meaning. RFC 1951 §3.2.5 says distance codes 30 and 31 never occur in data, so that's a fatal error. expected: must-reject, does not conform spec: RFC 1951 §3.2.6 no reference pixels1: upng-head	R	R	R	R	R	R	R	R	R	R	R	R	R	R	R	R	R	R	R	R	R	R	R	R	R	R	R	R	R	R	R	R	R	A	R	R	R
y_deflate-zopflipng IHDRIDATIEND the rgba16 picture written by zopfli: dynamic blocks and real matches. expected: display, conforms spec: RFC 1951 §3.2.7 expected38 match matches the reference; color under alpha 0 preserved; 16→8 high byte6: upng, pillow, chunky_png, upng-head, pillow-head, chunky_png-head	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓
y_deflate-libdeflatepng IHDRIDATIEND the rgba16 picture written by libdeflate: dynamic blocks and real matches. expected: display, conforms spec: RFC 1951 §3.2.7 expected38 match matches the reference; color under alpha 0 preserved; 16→8 high byte6: upng, pillow, chunky_png, upng-head, pillow-head, chunky_png-head	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓
y_deflate-7-zippng IHDRIDATIEND the rgba16 picture written by 7-zip: dynamic blocks and real matches. expected: display, conforms spec: RFC 1951 §3.2.7 expected38 match matches the reference; color under alpha 0 preserved; 16→8 high byte6: upng, pillow, chunky_png, upng-head, pillow-head, chunky_png-head	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓
i_deflate-empty-dynamic-blockpng IHDRIDATIEND the image data in a non-final stored block, then a final dynamic block that is empty: its literal/length code is the single one-bit code for 256, and it has no distance code. RFC 1951 §3.2.2 doesn't describe a one-code literal/length alphabet; a decoder may reject it or decode it, and zlib decodes it. RFC 1951 §3.2.7 says one zero-length distance code means the block doesn't use distance codes at all. expected: may-reject, does not conform spec: RFC 1951 §3.2.3 expected40 match	✓	✓	A	A	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	R	R	✓	✓	✓	R	✓	✓
n_ihdr-len-12png IHDRIDATIEND IHDR one byte short. §11.2.1 says IHDR is 13 bytes; §13.2 says a decoder should treat a wrong length as an error. expected: must-reject, does not conform no reference pixels2: upng, upng-head no reference pixels2: chunky_png, chunky_png-head	R	R	R	R	A	R	R	R	R	R	R	R	R	R	R	R	R	R	R	R	R	R	R	R	R	R	R	R	R	R	R	R	A	A	R	R	R
n_ihdr-len-14png IHDRIDATIEND IHDR one byte long. §11.2.1 says IHDR is 13 bytes; §13.2 says a decoder should treat a wrong length as an error. expected: must-reject, does not conform no reference pixels10: imagesharp, pngjs, upng, pillow, chunky_png, imagesharp-head, pngjs-head, upng-head, pillow-head, chunky_png-head	R	R	R	R	A	R	R	R	R	R	R	R	R	A	R	R	R	R	R	R	R	A	A	A	A	R	R	R	R	R	R	R	A	A	R	R	R
n_ihdr-compression-1png IHDRIDATIEND compression method 1; data is ordinary zlib. §11.2.1 defines only compression method 0; a decoder must report any other as an error. expected: must-reject, does not conform spec: §13.2 no reference pixels7: imagesharp, pillow, chunky_png, imagesharp-head, upng-head, pillow-head, chunky_png-head no reference pixels1: upng	R	R	R	R	A	R	R	R	R	R	R	R	R	A	R	R	R	R	R	R	R	A	A	R	R	R	R	R	R	R	R	R	A	A	R	R	R
n_ihdr-filter-1png IHDRIDATIEND filter method 1; data uses filter method 0. §11.2.1 defines only filter method 0; any other is an error. expected: must-reject, does not conform spec: §15.3.3 no reference pixels8: ffmpeg, zune-png, upng, chunky_png, ffmpeg-head, zune-png-head, upng-head, chunky_png-head	R	R	R	R	A	R	A	A	R	R	R	R	R	R	R	R	R	R	R	R	R	R	R	R	R	R	R	R	R	R	R	R	A	A	R	A	A
n_ihdr-interlace-2png IHDRIDATIEND interlace method 2; data is non-interlaced. §11.2.1 defines interlace methods 0 and 1; any other is an error. expected: must-reject, does not conform spec: §15.3.3 no reference pixels2: upng, upng-head no reference pixels2: ffmpeg, ffmpeg-head	R	R	R	R	R	R	A	A	R	R	R	R	R	R	R	R	R	R	R	R	R	R	R	R	R	R	R	R	R	R	R	R	A	A	R	R	R
n_ihdr-width-0png IHDRIDATIEND width 0. §11.2.1 says zero is an invalid dimension, so that's a fatal error. expected: must-reject, does not conform	R	R	R	R	R	R	R	R	R	R	R	R	R	R	R	R	R	R	R	R	R	R	R	R	R	R	R	R	R	R	R	R	!	!	R	R	R
n_ihdr-height-0png IHDRIDATIEND height 0. §11.2.1 says zero is an invalid dimension, so that's a fatal error. expected: must-reject, does not conform	R	R	R	R	R	!	R	R	R	R	R	R	R	R	R	R	R	R	R	R	R	R	R	R	R	R	R	!	!	R	R	R	!	!	R	R	R
n_ihdr-width-2-31png IHDRIDATIEND width 2^31, beyond the PNG integer range. §7.1 limits dimensions to 2^31−1, so that's a fatal error. expected: must-reject, does not conform spec: §11.2.1	R	R	R	R	R	∞	R	R	R	R	R	R	R	R	R	R	R	R	∞	R	R	R	R	R	R	R	R	∞	∞	R	R	R	⧗	∞	R	R	R
n_ihdr-both-0png IHDRIDATIEND 0x0 image with an empty zlib stream. §11.2.1 says zero is an invalid dimension, so that's a fatal error. expected: must-reject, does not conform	R	R	R	R	R	!	R	R	R	R	R	R	R	R	R	R	R	R	R	R	R	R	R	R	R	R	R	!	!	R	R	R	!	!	R	R	R
n_ihdr-rgb-bd4png IHDRIDATIEND color type 2 at bit depth 4 is not an allowed combination; the picture quantized to 4 bits. Table 12 in §11.2.1 lists the allowed color type and bit depth pairs; any other is an error. expected: must-reject, does not conform spec: Table 12, §13 no reference pixels3: zune-png, pngjs, pngjs-head no reference pixels2: fast-png, fast-png-head no reference pixels2: upng, upng-head no reference pixels2: stb_image, stb_image-head no reference pixels2: ffmpeg, ffmpeg-head no reference pixels1: zune-png-head	R	R	R	R	R	A	A	A	R	R	R	R	R	R	R	R	R	R	R	R	R	R	R	A	A	R	R	R	R	R	R	A	A	A	R	A	A
n_ihdr-rgb-bd1png IHDRIDATIEND color type 2 at bit depth 1 is not an allowed combination; the picture quantized to 1 bits. Table 12 in §11.2.1 lists the allowed color type and bit depth pairs; any other is an error. expected: must-reject, does not conform spec: Table 12, §13 no reference pixels3: zune-png, pngjs, pngjs-head no reference pixels2: fast-png, fast-png-head no reference pixels2: upng, upng-head no reference pixels2: stb_image, stb_image-head no reference pixels1: zune-png-head	R	R	R	R	R	A	R	R	R	R	R	R	R	R	R	R	R	R	R	R	R	R	R	A	A	R	R	R	R	R	R	A	A	A	R	A	A
n_ihdr-ga-bd4png IHDRIDATIEND color type 4 at bit depth 4 is not an allowed combination; the picture quantized to 4 bits. Table 12 in §11.2.1 lists the allowed color type and bit depth pairs; any other is an error. expected: must-reject, does not conform spec: Table 12, §13 no reference pixels3: fast-png, zune-png-head, fast-png-head no reference pixels3: zune-png, pngjs, pngjs-head no reference pixels2: upng, upng-head no reference pixels2: stb_image, stb_image-head	R	R	R	R	R	A	R	R	R	R	R	R	R	R	R	R	R	R	R	R	R	R	R	A	A	R	R	R	R	R	R	A	A	A	R	A	A
n_ihdr-rgba-bd2png IHDRIDATIEND color type 6 at bit depth 2 is not an allowed combination; the picture quantized to 2 bits. Table 12 in §11.2.1 lists the allowed color type and bit depth pairs; any other is an error. expected: must-reject, does not conform spec: Table 12, §13 no reference pixels3: zune-png, pngjs, pngjs-head no reference pixels2: stb_image, stb_image-head no reference pixels2: upng, upng-head no reference pixels2: ffmpeg, ffmpeg-head no reference pixels2: fast-png, fast-png-head no reference pixels1: zune-png-head	R	R	R	R	R	A	A	A	R	R	R	R	R	R	R	R	R	R	R	R	R	R	R	A	A	R	R	R	R	R	R	A	A	A	R	A	A
n_ihdr-g-bd3png IHDRIDATIEND color type 0 at bit depth 3 is not an allowed combination; the picture's 8-bit samples, laid out as 8-bit. §11.2.1 lists the valid bit depths; any other is an error. expected: must-reject, does not conform spec: §15.3.3 no reference pixels2: upng, upng-head	R	R	R	R	R	R	R	R	R	R	R	R	R	R	R	R	R	R	R	R	R	R	R	R	R	R	R	R	R	R	R	R	A	A	R	R	R
n_ihdr-g-bd0png IHDRIDATIEND color type 0 at bit depth 0 is not an allowed combination; the picture's 8-bit samples, laid out as 8-bit. §11.2.1 lists the valid bit depths; any other is an error. expected: must-reject, does not conform spec: §15.3.3 no reference pixels2: upng, upng-head	R	R	R	R	R	R	R	R	R	R	R	R	R	R	R	R	R	R	R	R	R	R	R	R	R	R	R	R	R	R	R	R	A	A	R	R	R
n_ihdr-p-bd16png IHDRPLTEIDATIEND color type 3 at bit depth 16 is not an allowed combination; the p8 indices as 16-bit samples. Table 12 in §11.2.1 lists the allowed color type and bit depth pairs; any other is an error. expected: must-reject, does not conform spec: Table 12, §13 no reference pixels2: upng, upng-head no reference pixels2: pngjs, pngjs-head	R	R	R	R	R	R	R	R	R	R	R	R	R	R	R	R	R	R	R	R	R	R	R	A	A	R	R	R	R	R	R	R	A	A	R	R	R
n_ihdr-ct1png IHDRIDATIEND color type 1 is undefined; data is 8-bit grayscale. §11.2.1 lists the valid color types; any other is an error. expected: must-reject, does not conform spec: §15.3.3 no reference pixels2: upng, upng-head	R	R	R	R	R	R	R	R	R	R	R	R	R	R	R	R	R	R	R	R	R	R	R	R	R	R	R	R	R	R	R	R	A	A	R	R	R
n_ihdr-ct5png IHDRIDATIEND color type 5 is undefined; data is 8-bit grayscale. §11.2.1 lists the valid color types; any other is an error. expected: must-reject, does not conform spec: §15.3.3 no reference pixels2: upng, upng-head	R	R	R	R	R	R	R	R	R	R	R	R	R	R	R	R	R	R	R	R	R	R	R	R	R	R	R	R	R	R	R	R	A	A	R	R	R
n_ihdr-ct7png IHDRIDATIEND color type 7 is undefined; data is 8-bit grayscale. §11.2.1 lists the valid color types; any other is an error. expected: must-reject, does not conform spec: §15.3.3 no reference pixels2: upng, upng-head	R	R	A	A	R	R	R	R	R	R	R	R	R	R	R	R	R	R	R	R	R	R	R	R	R	R	R	R	R	R	R	R	A	A	R	R	R
n_ihdr-not-firstpng tEXtIHDRIDATIEND a tEXt chunk precedes IHDR. §11.2.1 says IHDR comes first, so that's a fatal error. expected: must-reject, does not conform spec: §5.6 expected16 match	R	R	R	R	A	A	A	A	A	R	R	R	R	A	R	R	R	R	R	R	R	A	A	R	R	R	R	A	A	R	R	R	A	A	R	R	R
n_ihdr-not-first-unknownpng prIvIHDRIDATIEND an unknown ancillary private chunk precedes IHDR. §11.2.1 says IHDR comes first, so that's a fatal error. expected: must-reject, does not conform spec: §5.6 expected21 match	R	R	R	R	A	A	A	A	A	R	R	R	R	A	R	A	A	R	R	R	R	A	A	R	R	A	A	A	A	R	R	R	A	A	R	R	R
n_ihdr-duppng IHDR ×2IDATIEND two identical IHDR chunks. §11.2 allows one IHDR, so that's a fatal error. expected: must-reject, does not conform spec: §5.6 expected13 match	R	R	R	R	A	A	R	R	R	R	R	R	R	R	A	R	R	R	R	R	R	A	A	A	A	R	R	A	A	R	R	R	A	A	R	R	R
n_ihdr-dup-differentpng IHDR ×2IDATIEND a second IHDR giving 2x2. §11.2 allows one IHDR, so that's a fatal error. expected: must-reject, does not conform spec: §5.6 expected1 match: java-imageio 2x2 instead of 13x151: upng-head 2x2 instead of 13x151: upng	R	R	R	R	R	R	R	R	R	R	R	R	R	R	A	R	R	R	R	R	R	R	R	R	R	R	R	R	R	R	R	R	A	A	R	R	R
n_ihdr-missingpng IDATIEND no IHDR at all. §11.2.1 says IHDR comes first, so that's a fatal error. expected: must-reject, does not conform spec: §5.6	R	R	R	R	R	R	R	R	R	R	R	R	R	R	R	R	R	R	R	R	R	R	R	R	R	R	R	R	R	R	R	R	!	!	R	R	R
n_plte-len-not-mult3-palpng IHDRPLTEIDATIEND palette length 109 in an indexed image. §11.2.2 says PLTE holds 1 to 256 entries of 3 bytes each; §13.1 says a viewer can't recover from an invalid one in an indexed image. expected: must-reject, does not conform no reference pixels11: lodepng, java-imageio, imagesharp, pngjs, upng, pillow, lodepng-head, imagesharp-head, pngjs-head, upng-head, pillow-head no reference pixels2: ffmpeg, ffmpeg-head	R	R	R	R	R	R	A	A	R	R	R	R	R	A	A	R	R	R	A	R	R	A	A	A	A	R	R	R	R	R	R	R	A	A	R	R	R
r_plte-len-not-mult3-rgbpng IHDRPLTEIDATIEND palette length 109 in a truecolor image, a suggested palette. §13.1 says a viewer can ignore an invalid PLTE in a truecolor image. expected: recover, does not conform spec: §11.2.2 expected31 match	✓	✓	R	R	✓	R	✓	✓	R	✓	✓	✓	✓	✓	✓	✓	✓	R	✓	✓	✓	✓	✓	✓	✓	✓	✓	R	R	✓	R	R	✓	✓	✓	R	R
n_plte-empty-palpng IHDRPLTEIDATIEND zero-length PLTE in an indexed image. §11.2.2 says PLTE holds 1 to 256 entries of 3 bytes each; §13.1 says a viewer can't recover from an invalid one in an indexed image. expected: must-reject, does not conform no reference pixels11: ffmpeg, wuffs, zune-png, java-imageio, upng, pillow, ffmpeg-head, wuffs-head, zune-png-head, upng-head, pillow-head	R	R	R	R	!	R	A	A	R	R	R	R	R	R	A	R	R	R	R	R	R	A	A	R	R	R	R	R	R	R	R	R	A	A	A	A	A
r_plte-empty-rgbpng IHDRPLTEIDATIEND zero-length PLTE in a truecolor image. §13.1 says a viewer can ignore an invalid PLTE in a truecolor image. expected: recover, does not conform spec: §11.2.2 expected23 match	✓	✓	R	R	✓	✓	✓	✓	R	R	R	R	R	✓	✓	R	R	R	R	R	R	✓	✓	✓	✓	R	R	R	R	R	R	✓	✓	✓	✓	✓	✓
i_plte-too-many-for-depthpng IHDRPLTEIDATIEND 1-bit indexed image with a 4-entry palette (p1's two entries, then black and white); only indices 0 and 1 are used. §11.2.2 says a palette has no more entries than the bit depth can index; a decoder may reject that or ignore the surplus. expected: may-reject, does not conform expected38 match	✓	✓	R	R	✓	✓	✓	✓	R	✓	✓	✓	✓	✓	✓	✓	✓	R	✓	✓	✓	✓	✓	✓	✓	✓	✓	R	R	✓	✓	✓	✓	✓	✓	✓	✓
n_plte-257-entriespng IHDRPLTEIDATIEND 771-byte PLTE: 257 entries (p8's 36, then black). §11.2.2 says PLTE holds 1 to 256 entries of 3 bytes each; §13.1 says a viewer can't recover from an invalid one in an indexed image. expected: must-reject, does not conform no reference pixels11: java-imageio, imagesharp, fast-png, pngjs, upng, chunky_png, imagesharp-head, fast-png-head, pngjs-head, upng-head, chunky_png-head no reference pixels2: ffmpeg, ffmpeg-head	R	R	R	R	A	A	A	A	R	R	R	R	R	A	A	R	R	R	R	R	R	R	R	A	A	R	R	R	R	R	R	R	A	A	R	R	R
i_plte-in-graypng IHDRPLTEIDATIEND PLTE in a grayscale image. §11.2.2 says PLTE must not appear in a grayscale image; a decoder may reject it or ignore it. expected: may-reject, does not conform expected38 match	✓	✓	R	R	✓	R	✓	✓	R	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	R	✓	✓
i_plte-in-grayapng IHDRPLTEIDATIEND PLTE in a grayscale+alpha image. §11.2.2 says PLTE must not appear in a grayscale image; a decoder may reject it or ignore it. expected: may-reject, does not conform expected40 match	✓	✓	R	R	✓	✓	✓	✓	R	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	R	✓	✓
n_plte-after-idat-palpng IHDRIDATPLTEIEND indexed image whose PLTE follows IDAT. §11.2.2 says an indexed image has a PLTE before IDAT, so that's a fatal error. expected: must-reject, does not conform spec: §11.2.1, §5.6 no reference pixels9: lodepng, zune-png, fast-png, upng, chunky_png, lodepng-head, fast-png-head, upng-head, chunky_png-head no reference pixels2: ffmpeg, ffmpeg-head no reference pixels2: pillow, pillow-head	R	R	R	R	A	A	A	A	R	R	R	R	R	R	R	R	R	R	A	R	R	A	A	R	R	R	R	R	R	R	R	R	A	A	R	A	R
r_plte-after-idat-rgbpng IHDRIDATPLTEIEND truecolor image with a suggested palette after IDAT. §13.1 says a viewer can ignore an invalid PLTE in a truecolor image. expected: recover, does not conform spec: §11.2.2 expected42 match	✓	✓	R	R	✓	✓	✓	✓	R	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓
i_plte-dup-rgbpng IHDRPLTE ×2IDATIEND two suggested palettes in a truecolor image. §11.2.2 allows one PLTE; a decoder may reject the file or carry on with one of them. expected: may-reject, does not conform expected38 match	✓	✓	R	R	✓	✓	✓	✓	R	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	R	R	✓	✓	✓	R	✓	✓
i_plte-crc-bad-rgbpng IHDRPLTEIDATIEND bad CRC on an unused suggested palette. §13.1 says a CRC mismatch may be fatal; a decoder that carries on uses the chunk as stored. expected: may-reject, does not conform spec: §5.5 expected27 match	✓	✓	R	R	R	✓	✓	✓	R	✓	✓	✓	✓	R	✓	✓	✓	R	R	✓	✓	R	R	R	R	✓	✓	R	✓	R	R	✓	✓	✓	✓	✓	✓
i_plte-crc-bad-palpng IHDRPLTEIDATIEND bad CRC on the palette of an indexed image. §13.1 says a CRC mismatch may be fatal; a decoder that carries on uses the chunk as stored. expected: may-reject, does not conform spec: §5.5 expected18 match	✓^c	✓^c	R	R	R	✓^c	✓^c	✓^c	R	✓^c	✓^c	R	R	R	✓^c	R	R	R	R	R	R	R	R	R	R	R	R	R	✓^c	R	R	✓^c	✓^c	✓^c	✓^c	✓^c	✓^c
r_plte-index-beyond-2bitpng IHDRPLTEIDATIEND p2 with its PLTE cut to three entries: 29 pixels use index 3. §13.1 requires a decoder to show a palette index past the end of PLTE as opaque black. expected: 2nd edition: must-reject, does not conform; 3rd edition: recover, does not conform spec: §11.2.2 expected27 match 29 of 195 pixels differ2: imagesharp, imagesharp-head 29 of 195 pixels differ2: stb_image, stb_image-head	RR	A✓	A	A	!	RR	A✓	A✓	A✓	RR	RR	RR	RR	A≠	A✓	A✓	A✓	A✓	A✓	A✓	A✓	A✓	A✓	RR	RR	A✓	A✓	RR	RR	A✓	A✓	M	A✓	A✓	A✓	A✓	A✓
r_plte-index-beyond-2bit-trnspng IHDRPLTEtRNSIDATIEND p2 with its PLTE cut to three entries: 29 pixels use index 3; tRNS 80 ff, and the out-of-range pixels stay opaque. §13.1 requires a decoder to show a palette index past the end of PLTE as opaque black. expected: 2nd edition: must-reject, does not conform; 3rd edition: recover, does not conform spec: §11.2.2 expected27 match 29 of 195 pixels differ2: imagesharp, imagesharp-head 29 of 195 pixels differ2: stb_image, stb_image-head	RR	A✓	A	A	!	RR	A✓	A✓	A✓	RR	RR	RR	RR	A≠	A✓	A✓	A✓	A✓	A✓	A✓	A✓	A✓	A✓	RR	RR	A✓	A✓	RR	RR	A✓	A✓	M	A✓	A✓	A✓	A✓	A✓
r_plte-index-beyond-1bitpng IHDRPLTEIDATIEND p1 with its PLTE cut to 1 of 2 entries: 101 pixels use an index past it. §13.1 requires a decoder to show a palette index past the end of PLTE as opaque black. expected: 2nd edition: must-reject, does not conform; 3rd edition: recover, does not conform spec: §11.2.2 expected29 match 101 of 195 pixels differ2: imagesharp, imagesharp-head	RR	A✓	A	A	!	RR	A✓	A✓	A✓	RR	RR	RR	RR	A≠	A✓	A✓	A✓	A✓	A✓	A✓	A✓	A✓	A✓	RR	RR	A✓	A✓	RR	RR	A✓	A✓	M	A✓	A✓	A✓	A✓	A✓
r_plte-index-beyond-4bitpng IHDRPLTEIDATIEND p4 with its PLTE cut to 15 of 16 entries: 8 pixels use an index past it. §13.1 requires a decoder to show a palette index past the end of PLTE as opaque black. expected: 2nd edition: must-reject, does not conform; 3rd edition: recover, does not conform spec: §11.2.2 expected27 match 8 of 195 pixels differ2: stb_image, stb_image-head 8 of 195 pixels differ2: imagesharp, imagesharp-head	RR	A✓	A	A	!	RR	A✓	A✓	A✓	RR	RR	RR	RR	A≠	A✓	A✓	A✓	A✓	A✓	A✓	A✓	A✓	A✓	RR	RR	A✓	A✓	RR	RR	A✓	A✓	M	A✓	A✓	A✓	A✓	A✓
r_plte-index-beyond-8bitpng IHDRPLTEIDATIEND p8 with its PLTE cut to 35 of 36 entries: 2 pixels use an index past it. §13.1 requires a decoder to show a palette index past the end of PLTE as opaque black. expected: 2nd edition: must-reject, does not conform; 3rd edition: recover, does not conform spec: §11.2.2 expected27 match 2 of 195 pixels differ2: imagesharp, imagesharp-head 2 of 195 pixels differ2: stb_image, stb_image-head	RR	A✓	A	A	!	RR	A✓	A✓	A✓	RR	RR	RR	RR	A≠	A✓	A✓	A✓	A✓	A✓	A✓	A✓	A✓	A✓	RR	RR	A✓	A✓	RR	RR	A✓	A✓	M	A✓	A✓	A✓	A✓	A✓
r_trns-len-1-graypng IHDRtRNSIDATIEND 1-byte tRNS on grayscale (should be 2). §11.3.1.1 fixes the tRNS length per color type; a decoder should ignore one of the wrong length. expected: recover, does not conform spec: §13.2 expected24 match	✓	✓	R	R	R	R	✓	✓	R	✓	✓	✓	✓	✓	✓	✓	✓	✓	R	✓	✓	R	R	R	R	✓	✓	R	R	✓	✓	R	✓	✓	R	R	R
r_trns-len-3-graypng IHDRtRNSIDATIEND 3-byte tRNS on grayscale. §11.3.1.1 fixes the tRNS length per color type; a decoder should ignore one of the wrong length. expected: recover, does not conform spec: §13.2 expected18 match the first two bytes taken as the gray value, so 149 is transparent9: rust-png, imagesharp, upng, pillow, rust-png-head, zune-png-head, imagesharp-head, upng-head, pillow-head the first two bytes taken as the gray value, so 149 is transparent; color under alpha 0 zeroed4: pngjs, chunky_png, pngjs-head, chunky_png-head	✓	✓	R	R	≠	R	✓	✓	R	✓	✓	✓	✓	≠	✓	✓	✓	✓	R	✓	✓	≠	≠	≠	≠	✓	✓	R	R	≠	≠	R	≠	≠	R	R	≠
r_trns-len-4-rgbpng IHDRtRNSIDATIEND 4-byte tRNS on truecolor (should be 6). §11.3.1.1 fixes the tRNS length per color type; a decoder should ignore one of the wrong length. expected: recover, does not conform spec: §13.2 expected26 match	✓	✓	R	R	R	✓	✓	✓	R	✓	✓	✓	✓	✓	✓	✓	✓	✓	R	✓	✓	R	R	R	R	✓	✓	R	R	✓	✓	R	✓	✓	R	R	R
r_trns-len-7-rgbpng IHDRtRNSIDATIEND 7-byte tRNS on truecolor. §11.3.1.1 fixes the tRNS length per color type; a decoder should ignore one of the wrong length. expected: recover, does not conform spec: §13.2 expected18 match the first six bytes taken as the color, so black is transparent13: rust-png, imagesharp, pngjs, upng, pillow, chunky_png, rust-png-head, zune-png-head, imagesharp-head, pngjs-head, upng-head, pillow-head, chunky_png-head	✓	✓	R	R	≠	R	✓	✓	R	✓	✓	✓	✓	≠	✓	✓	✓	✓	R	✓	✓	≠	≠	≠	≠	✓	✓	R	R	≠	≠	R	≠	≠	R	R	≠
y_trns-len-0-palpng IHDRPLTEtRNSIDATIEND zero-length tRNS on an indexed image: every entry stays opaque. §11.3.1.1 says tRNS may cover fewer entries than the palette has; the rest are opaque. expected: display, conforms expected44 match	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓
r_trns-longer-than-pltepng IHDRPLTEtRNSIDATIEND 6 alpha values for a 4-entry palette. §11.3.1.1 fixes the tRNS length per color type; a decoder should ignore one of the wrong length. expected: recover, does not conform spec: §13.2 expected17 match the alpha values that have palette entries applied, the extra ones dropped15: ffmpeg, wuffs, zune-png, go-png, java-imageio, upng, pillow, chunky_png, ffmpeg-head, wuffs-head, zune-png-head, upng-head, pillow-head, chunky_png-head, go-png-head	✓	✓	R	R	≠	R	≠	≠	≠	✓	✓	✓	✓	R	≠	✓	✓	✓	R	✓	✓	≠	≠	R	R	✓	✓	R	R	✓	✓	R	≠	≠	≠	≠	≠
r_trns-in-grayapng IHDRtRNSIDATIEND tRNS in a grayscale+alpha image. §11.3.1.1 says tRNS must not appear in an image with an alpha channel; a decoder should ignore it. expected: recover, does not conform expected31 match	✓	✓	R	R	✓	R	✓	✓	R	✓	✓	✓	✓	✓	R	✓	✓	✓	R	✓	✓	✓	✓	✓	✓	✓	✓	R	R	✓	✓	R	✓	✓	✓	R	R
r_trns-in-rgbapng IHDRtRNSIDATIEND tRNS in a truecolor+alpha image. §11.3.1.1 says tRNS must not appear in an image with an alpha channel; a decoder should ignore it. expected: recover, does not conform expected31 match	✓	✓	R	R	✓	R	✓	✓	R	✓	✓	✓	✓	✓	R	✓	✓	✓	R	✓	✓	✓	✓	✓	✓	✓	✓	R	R	✓	✓	R	✓	✓	✓	R	R
r_trns-after-idat-graypng IHDRIDATtRNSIEND tRNS after IDAT on grayscale (value 149 is the commonest gray of the picture). Table 7 in §5.6 puts this chunk after PLTE and before IDAT; a decoder should ignore a misplaced one. expected: recover, does not conform spec: Table 7 expected29 match the misplaced tRNS applied7: lodepng, zune-png, upng, pillow, lodepng-head, upng-head, pillow-head the misplaced tRNS applied; color under alpha 0 zeroed4: pngjs, chunky_png, pngjs-head, chunky_png-head	✓	✓	R	R	≠	✓	✓	✓	R	✓	✓	✓	✓	✓	✓	✓	✓	✓	≠	✓	✓	≠	≠	≠	≠	✓	✓	✓	✓	✓	✓	R	≠	≠	✓	≠	✓
r_trns-after-idat-palpng IHDRPLTEIDATtRNSIEND tRNS after IDAT on an indexed image. Table 7 in §5.6 puts this chunk after PLTE and before IDAT; a decoder should ignore a misplaced one. expected: recover, does not conform spec: Table 7 expected26 match the misplaced tRNS applied14: lodepng, zune-png, java-imageio, fast-png, pngjs, upng, pillow, chunky_png, lodepng-head, fast-png-head, pngjs-head, upng-head, pillow-head, chunky_png-head	✓	✓	R	R	≠	≠	✓	✓	R	✓	✓	✓	✓	✓	≠	✓	✓	✓	≠	✓	✓	≠	≠	≠	≠	✓	✓	✓	✓	✓	✓	R	≠	≠	✓	≠	✓
r_trns-before-plte-palpng IHDRtRNSPLTEIDATIEND tRNS before PLTE on an indexed image. Table 7 in §5.6 puts this chunk after PLTE and before IDAT; a decoder should ignore a misplaced one. expected: recover, does not conform spec: Table 7 expected19 match the misplaced tRNS applied10: imagesharp, upng, pillow, pypng, chunky_png, imagesharp-head, upng-head, pillow-head, pypng-head, chunky_png-head	✓	✓	R	R	≠	R	✓	✓	R	✓	✓	✓	✓	≠	R	✓	✓	✓	R	✓	✓	≠	≠	R	R	✓	✓	≠	≠	✓	✓	R	≠	≠	R	R	R
r_trns-before-plte-rgbpng IHDRtRNSPLTEIDATIEND tRNS naming the top-left pixel's color, then a suggested palette, on a truecolor image: tRNS is before PLTE. Table 7 in §5.6 puts this chunk after PLTE and before IDAT; a decoder should ignore a misplaced one. expected: recover, does not conform spec: Table 7 expected28 match matches the reference; color under alpha 0 zeroed6: wuffs, pngjs, chunky_png, wuffs-head, pngjs-head, chunky_png-head the misplaced tRNS ignored6: fast-png, pngtopam, graphicsmagick, graphicsmagick-head, fast-png-head, pngtopam-head	✓	✓	A	A	✓	≠	✓	✓	R	≠	≠	✓	✓	✓	✓	✓	✓	R	✓	✓	✓	✓	✓	✓	✓	≠	M	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓
r_trns-dup-graypng IHDRtRNS ×2IDATIEND two tRNS chunks naming the picture's two commonest grays, 149 and 34; expected pixels: the first applied. Table 7 in §5.6 allows this chunk once; a decoder should ignore the second. expected: recover, does not conform spec: Table 7, §13.1 expected15 match: reference-2, reference-3, libpng, rust-png, imagemagick, libspng, pngtopam, graphicsmagick, libpng16-head, libpng18-head, rust-png-head, imagemagick-head, graphicsmagick-head, libspng-head, pngtopam-head matches trns:last (arguable: one of several tRNS chunks used); color under alpha 0 preserved17: stb_image, ffmpeg, lodepng, zune-png, java-imageio, imagesharp, upng, pillow, pypng, stb_image-head, ffmpeg-head, lodepng-head, zune-png-head, imagesharp-head, upng-head, pillow-head, pypng-head neither tRNS applied4: fast-png, opencv, fast-png-head, opencv-head matches trns:last (arguable: one of several tRNS chunks used); color under alpha 0 zeroed4: pngjs, chunky_png, pngjs-head, chunky_png-head	✓^t	✓^t	R	R	✓^t	≠	✓^t	✓^t	R	✓^t	✓^t	✓^t	✓^t	✓^t	✓^t	✓^t	✓^t	✓^t	✓^t	≠	≠	✓^t	✓^t	✓^t	✓^t	✓^t	✓^t	✓^t	✓^t	✓^t	✓^t	✓^t	✓^t	✓^t	R	✓^t	✓^t
y_trns-g4-highbitspng IHDRtRNSIDATIEND 4-bit gray, tRNS 0x00F6: masked to 0x6. §11.3.1.1 says a decoder masks a tRNS value to the bit depth before using it. expected: display, conforms expected7 match: reference-2, reference-3, libpng, zune-png, libpng16-head, libpng18-head, zune-png-head tRNS compared without masking: nothing matches, nothing is transparent34: stb_image, rust-png, ffmpeg, imagemagick, lodepng, libspng, go-png, java-imageio, imagesharp, fast-png, pngjs, pillow, pypng, opencv, chunky_png, pngtopam, graphicsmagick, stb_image-head, rust-png-head, ffmpeg-head, imagemagick-head, graphicsmagick-head, lodepng-head, libspng-head, imagesharp-head, fast-png-head, pngjs-head, upng-head, pillow-head, pypng-head, opencv-head, chunky_png-head, pngtopam-head, go-png-head matches the reference; color under alpha 0 zeroed2: wuffs, wuffs-head 129 of 195 pixels differ1: upng	✓	✓	✓	✓	≠	≠	≠	≠	≠	≠	≠	≠	≠	≠	≠	✓	✓	≠	≠	≠	≠	≠	≠	≠	≠	≠	≠	≠	≠	≠	≠	≠	≠	≠	✓	✓	✓
y_trns-g4-highbytepng IHDRtRNSIDATIEND 4-bit gray, tRNS 0x0106: masked to 0x6. §11.3.1.1 says a decoder masks a tRNS value to the bit depth before using it. expected: display, conforms expected15 match: reference-2, reference-3, libpng, stb_image, rust-png, zune-png, go-png, imagesharp, libpng16-head, libpng18-head, stb_image-head, rust-png-head, zune-png-head, imagesharp-head, go-png-head tRNS compared without masking: nothing matches, nothing is transparent26: ffmpeg, imagemagick, lodepng, libspng, java-imageio, fast-png, pngjs, pillow, pypng, opencv, chunky_png, pngtopam, graphicsmagick, ffmpeg-head, imagemagick-head, graphicsmagick-head, lodepng-head, libspng-head, fast-png-head, pngjs-head, upng-head, pillow-head, pypng-head, opencv-head, chunky_png-head, pngtopam-head matches the reference; color under alpha 0 zeroed2: wuffs, wuffs-head 129 of 195 pixels differ1: upng	✓	✓	✓	✓	≠	≠	≠	≠	✓	≠	≠	≠	≠	✓	≠	✓	✓	≠	≠	≠	≠	≠	≠	≠	≠	≠	≠	≠	≠	✓	✓	✓	≠	≠	✓	✓	✓
y_trns-g8-highbytepng IHDRtRNSIDATIEND 8-bit gray, tRNS 0x0195: masked to 0x95. §11.3.1.1 says a decoder masks a tRNS value to the bit depth before using it. expected: display, conforms expected19 match: reference-2, reference-3, libpng, stb_image, rust-png, ffmpeg, zune-png, go-png, imagesharp, pillow, libpng16-head, libpng18-head, stb_image-head, rust-png-head, ffmpeg-head, zune-png-head, imagesharp-head, pillow-head, go-png-head tRNS compared without masking: nothing matches, nothing is transparent23: imagemagick, lodepng, libspng, java-imageio, fast-png, pngjs, upng, pypng, opencv, chunky_png, pngtopam, graphicsmagick, imagemagick-head, graphicsmagick-head, lodepng-head, libspng-head, fast-png-head, pngjs-head, upng-head, pypng-head, opencv-head, chunky_png-head, pngtopam-head matches the reference; color under alpha 0 zeroed2: wuffs, wuffs-head	✓	✓	✓	✓	≠	≠	✓	✓	✓	≠	≠	≠	≠	✓	≠	✓	✓	≠	≠	≠	≠	✓	✓	≠	≠	≠	≠	≠	≠	✓	✓	✓	≠	≠	✓	✓	✓
y_trns-g1-value-2png IHDRtRNSIDATIEND 1-bit gray, tRNS 0x0002: masked to 0, so black is transparent (not 'nonzero means white'). §11.3.1.1 says a decoder masks a tRNS value to the bit depth before using it. expected: display, conforms expected11 match: reference-2, reference-3, libpng, wuffs, zune-png, chunky_png, libpng16-head, libpng18-head, wuffs-head, zune-png-head, chunky_png-head tRNS compared without masking: nothing matches, nothing is transparent30: stb_image, rust-png, ffmpeg, imagemagick, lodepng, libspng, go-png, java-imageio, imagesharp, fast-png, pngjs, pypng, opencv, pngtopam, graphicsmagick, stb_image-head, rust-png-head, ffmpeg-head, imagemagick-head, graphicsmagick-head, lodepng-head, libspng-head, imagesharp-head, fast-png-head, pngjs-head, upng-head, pypng-head, opencv-head, pngtopam-head, go-png-head a nonzero tRNS value taken as white, so white is transparent2: pillow, pillow-head 174 of 195 pixels differ1: upng	✓	✓	✓	✓	✓	≠	≠	≠	≠	≠	≠	≠	≠	≠	≠	✓	✓	≠	≠	≠	≠	≠	≠	≠	≠	≠	≠	≠	≠	≠	≠	≠	≠	≠	✓	✓	✓
y_trns-g1-value-3png IHDRtRNSIDATIEND 1-bit gray, tRNS 0x0003: masked to 1, white transparent. §11.3.1.1 says a decoder masks a tRNS value to the bit depth before using it. expected: display, conforms expected9 match: reference-2, reference-3, libpng, zune-png, pillow, libpng16-head, libpng18-head, zune-png-head, pillow-head tRNS compared without masking: nothing matches, nothing is transparent30: stb_image, rust-png, ffmpeg, imagemagick, lodepng, libspng, go-png, java-imageio, imagesharp, fast-png, pngjs, pypng, opencv, pngtopam, graphicsmagick, stb_image-head, rust-png-head, ffmpeg-head, imagemagick-head, graphicsmagick-head, lodepng-head, libspng-head, imagesharp-head, fast-png-head, pngjs-head, upng-head, pypng-head, opencv-head, pngtopam-head, go-png-head matches the reference; color under alpha 0 zeroed2: wuffs, wuffs-head a tRNS value other than 1 taken as black, so black is transparent2: chunky_png, chunky_png-head 115 of 195 pixels differ1: upng	✓	✓	✓	✓	≠	≠	≠	≠	≠	≠	≠	≠	≠	≠	≠	✓	✓	≠	≠	≠	≠	✓	✓	≠	≠	≠	≠	≠	≠	≠	≠	≠	≠	≠	✓	✓	✓
y_trns-g2-value-5png IHDRtRNSIDATIEND 2-bit gray, tRNS 5: masked to 1. §11.3.1.1 says a decoder masks a tRNS value to the bit depth before using it. expected: display, conforms expected7 match: reference-2, reference-3, libpng, zune-png, libpng16-head, libpng18-head, zune-png-head tRNS compared without masking: nothing matches, nothing is transparent34: stb_image, rust-png, ffmpeg, imagemagick, lodepng, libspng, go-png, java-imageio, imagesharp, fast-png, pngjs, pillow, pypng, opencv, chunky_png, pngtopam, graphicsmagick, stb_image-head, rust-png-head, ffmpeg-head, imagemagick-head, graphicsmagick-head, lodepng-head, libspng-head, imagesharp-head, fast-png-head, pngjs-head, upng-head, pillow-head, pypng-head, opencv-head, chunky_png-head, pngtopam-head, go-png-head matches the reference; color under alpha 0 zeroed2: wuffs, wuffs-head 164 of 195 pixels differ1: upng	✓	✓	✓	✓	≠	≠	≠	≠	≠	≠	≠	≠	≠	≠	≠	✓	✓	≠	≠	≠	≠	≠	≠	≠	≠	≠	≠	≠	≠	≠	≠	≠	≠	≠	✓	✓	✓
y_trns-rgb8-highbytepng IHDRtRNSIDATIEND 8-bit RGB, tRNS with a set high byte in each sample: masked, the top-left pixel's color transparent. §11.3.1.1 says a decoder masks a tRNS value to the bit depth before using it. expected: display, conforms expected23 match tRNS compared without masking: nothing matches, nothing is transparent19: imagemagick, lodepng, java-imageio, fast-png, pngjs, upng, pypng, chunky_png, pngtopam, graphicsmagick, imagemagick-head, graphicsmagick-head, lodepng-head, fast-png-head, pngjs-head, upng-head, pypng-head, chunky_png-head, pngtopam-head matches the reference; color under alpha 0 zeroed2: wuffs, wuffs-head	✓	✓	✓	✓	≠	≠	✓	✓	✓	≠	≠	≠	≠	✓	≠	✓	✓	✓	≠	✓	✓	✓	✓	≠	≠	≠	≠	≠	≠	✓	✓	✓	≠	≠	✓	✓	✓
y_trns-rgb8-1x1png IHDRtRNSIDATIEND 1x1 truecolor with a tRNS naming its only pixel. expected: display, conforms spec: §11.3.1.1 expected32 match matches the reference; color under alpha 0 zeroed6: wuffs, pngjs, chunky_png, wuffs-head, pngjs-head, chunky_png-head 1 of 1 pixels differ4: pngtopam, graphicsmagick, graphicsmagick-head, pngtopam-head	✓	✓	✓	✓	✓	R	✓	✓	✓	≠	≠	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	≠	M	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓
y_trns-rgb8-2x1png IHDRtRNSIDATIEND 2x1 truecolor with a tRNS naming its pixels' color: fewer pixels than tRNS samples. expected: display, conforms spec: §11.3.1.1 expected32 match matches the reference; color under alpha 0 zeroed6: wuffs, pngjs, chunky_png, wuffs-head, pngjs-head, chunky_png-head 2 of 2 pixels differ4: pngtopam, graphicsmagick, graphicsmagick-head, pngtopam-head	✓	✓	✓	✓	✓	R	✓	✓	✓	≠	≠	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	≠	M	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓
y_trns-rgb16-1x1png IHDRtRNSIDATIEND 1x1 16-bit truecolor with tRNS naming its pixel. expected: display, conforms spec: §11.3.1.1 expected27 match 1 of 1 pixels differ5: zune-png, imagesharp, pngtopam, imagesharp-head, pngtopam-head matches the reference; color under alpha 0 zeroed4: wuffs, pngjs, wuffs-head, pngjs-head matches the reference; color under alpha 0 zeroed; 16→8 high byte2: chunky_png, chunky_png-head matches the reference; color under alpha 0 preserved; 16→8 high byte2: upng, upng-head 1 of 1 pixels differ2: pillow, pillow-head	✓	✓	✓	✓	✓	R	✓	✓	✓	✓	✓	✓	✓	≠	✓	✓	✓	✓	✓	✓	✓	≠	≠	✓	✓	≠	M	✓	✓	✓	✓	✓	✓	✓	✓	≠	✓
y_trns-g1-blackpng IHDRtRNSIDATIEND tRNS names black (0), a color of the picture: those pixels have alpha 0. expected: display, conforms spec: §11.3.1.1 expected36 match 118 of 195 pixels differ7: ffmpeg, fast-png, opencv, ffmpeg-head, fast-png-head, upng-head, opencv-head 174 of 195 pixels differ1: upng	✓	✓	✓	✓	✓	≠	≠	≠	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	≠	≠	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	≠	≠	✓	✓	✓
y_trns-g1-whitepng IHDRtRNSIDATIEND tRNS names white (1), a color of the picture: those pixels have alpha 0. expected: display, conforms spec: §11.3.1.1 expected30 match 77 of 195 pixels differ7: ffmpeg, java-imageio, fast-png, opencv, ffmpeg-head, fast-png-head, opencv-head matches the reference; color under alpha 0 zeroed6: wuffs, pngjs, chunky_png, wuffs-head, pngjs-head, chunky_png-head 94 of 195 pixels differ1: upng	✓	✓	✓	✓	✓	≠	≠	≠	✓	✓	✓	✓	✓	✓	≠	✓	✓	✓	✓	≠	≠	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	≠	✓	✓	✓	✓
y_trns-g2-blackpng IHDRtRNSIDATIEND tRNS names black (0), a color of the picture: those pixels have alpha 0. expected: display, conforms spec: §11.3.1.1 expected38 match 15 of 195 pixels differ5: fast-png, opencv, fast-png-head, upng-head, opencv-head 131 of 195 pixels differ1: upng	✓	✓	✓	✓	✓	≠	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	≠	≠	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	≠	≠	✓	✓	✓
y_trns-g2-whitepng IHDRtRNSIDATIEND tRNS names white (3), a color of the picture: those pixels have alpha 0. expected: display, conforms spec: §11.3.1.1 expected28 match 9 of 195 pixels differ9: ffmpeg, java-imageio, fast-png, pillow, opencv, ffmpeg-head, fast-png-head, pillow-head, opencv-head matches the reference; color under alpha 0 zeroed6: wuffs, pngjs, chunky_png, wuffs-head, pngjs-head, chunky_png-head 118 of 195 pixels differ1: upng	✓	✓	✓	✓	✓	≠	≠	≠	✓	✓	✓	✓	✓	✓	≠	✓	✓	✓	✓	≠	≠	≠	≠	✓	✓	✓	✓	✓	✓	✓	✓	✓	≠	✓	✓	✓	✓
y_trns-g2-midpng IHDRtRNSIDATIEND tRNS names mid (1), a color of the picture: those pixels have alpha 0. expected: display, conforms spec: §11.3.1.1 expected28 match 103 of 195 pixels differ9: ffmpeg, java-imageio, fast-png, pillow, opencv, ffmpeg-head, fast-png-head, pillow-head, opencv-head matches the reference; color under alpha 0 zeroed6: wuffs, pngjs, chunky_png, wuffs-head, pngjs-head, chunky_png-head 118 of 195 pixels differ1: upng	✓	✓	✓	✓	✓	≠	≠	≠	✓	✓	✓	✓	✓	✓	≠	✓	✓	✓	✓	≠	≠	≠	≠	✓	✓	✓	✓	✓	✓	✓	✓	✓	≠	✓	✓	✓	✓
y_trns-g4-blackpng IHDRtRNSIDATIEND tRNS names black (0), a color of the picture: those pixels have alpha 0. expected: display, conforms spec: §11.3.1.1 expected38 match 2 of 195 pixels differ5: fast-png, opencv, fast-png-head, upng-head, opencv-head 122 of 195 pixels differ1: upng	✓	✓	✓	✓	✓	≠	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	≠	≠	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	≠	≠	✓	✓	✓
y_trns-g4-whitepng IHDRtRNSIDATIEND tRNS names white (15), a color of the picture: those pixels have alpha 0. expected: display, conforms spec: §11.3.1.1 expected28 match 1 of 195 pixels differ9: ffmpeg, java-imageio, fast-png, pillow, opencv, ffmpeg-head, fast-png-head, pillow-head, opencv-head matches the reference; color under alpha 0 zeroed6: wuffs, pngjs, chunky_png, wuffs-head, pngjs-head, chunky_png-head 122 of 195 pixels differ1: upng	✓	✓	✓	✓	✓	≠	≠	≠	✓	✓	✓	✓	✓	✓	≠	✓	✓	✓	✓	≠	≠	≠	≠	✓	✓	✓	✓	✓	✓	✓	✓	✓	≠	✓	✓	✓	✓
y_trns-g4-midpng IHDRtRNSIDATIEND tRNS names mid (6), a color of the picture: those pixels have alpha 0. expected: display, conforms spec: §11.3.1.1 expected28 match 26 of 195 pixels differ9: ffmpeg, java-imageio, fast-png, pillow, opencv, ffmpeg-head, fast-png-head, pillow-head, opencv-head matches the reference; color under alpha 0 zeroed6: wuffs, pngjs, chunky_png, wuffs-head, pngjs-head, chunky_png-head 122 of 195 pixels differ1: upng	✓	✓	✓	✓	✓	≠	≠	≠	✓	✓	✓	✓	✓	✓	≠	✓	✓	✓	✓	≠	≠	≠	≠	✓	✓	✓	✓	✓	✓	✓	✓	✓	≠	✓	✓	✓	✓
y_trns-g8-blackpng IHDRtRNSIDATIEND tRNS names black (0), a color of the picture: those pixels have alpha 0. expected: display, conforms spec: §11.3.1.1 expected38 match 2 of 195 pixels differ6: fast-png, upng, opencv, fast-png-head, upng-head, opencv-head	✓	✓	✓	✓	✓	≠	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	≠	≠	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	≠	≠	✓	✓	✓
y_trns-g8-whitepng IHDRtRNSIDATIEND tRNS names white (255), a color of the picture: those pixels have alpha 0. expected: display, conforms spec: §11.3.1.1 expected34 match matches the reference; color under alpha 0 zeroed6: wuffs, pngjs, chunky_png, wuffs-head, pngjs-head, chunky_png-head 1 of 195 pixels differ4: fast-png, opencv, fast-png-head, opencv-head	✓	✓	✓	✓	✓	≠	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	≠	≠	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓
y_trns-g8-midpng IHDRtRNSIDATIEND tRNS names mid (149), a color of the picture: those pixels have alpha 0. expected: display, conforms spec: §11.3.1.1 expected34 match matches the reference; color under alpha 0 zeroed6: wuffs, pngjs, chunky_png, wuffs-head, pngjs-head, chunky_png-head 18 of 195 pixels differ4: fast-png, opencv, fast-png-head, opencv-head	✓	✓	✓	✓	✓	≠	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	≠	≠	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓
y_trns-g16-blackpng IHDRtRNSIDATIEND tRNS names black (0), a color of the picture: those pixels have alpha 0. expected: display, conforms spec: §11.3.1.1 expected34 match 2 of 195 pixels differ6: fast-png, pillow, opencv, fast-png-head, pillow-head, opencv-head matches the reference; 16→8 high byte2: chunky_png, chunky_png-head 194 of 195 pixels differ2: upng, upng-head	✓	✓	✓	✓	✓	≠	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	≠	≠	≠	≠	✓	✓	✓	✓	✓	✓	✓	✓	✓	≠	≠	✓	✓	✓
y_trns-g16-whitepng IHDRtRNSIDATIEND tRNS names white (65535), a color of the picture: those pixels have alpha 0. expected: display, conforms spec: §11.3.1.1 expected30 match 1 of 195 pixels differ6: fast-png, pillow, opencv, fast-png-head, pillow-head, opencv-head matches the reference; color under alpha 0 zeroed4: wuffs, pngjs, wuffs-head, pngjs-head matches the reference; color under alpha 0 zeroed; 16→8 high byte2: chunky_png, chunky_png-head matches the reference; color under alpha 0 preserved; 16→8 high byte2: upng, upng-head	✓	✓	✓	✓	✓	≠	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	≠	≠	≠	≠	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓
y_trns-g16-midpng IHDRtRNSIDATIEND tRNS names mid (8687), a color of the picture: those pixels have alpha 0. expected: display, conforms spec: §11.3.1.1 expected27 match 13 of 195 pixels differ9: zune-png, imagesharp, fast-png, pillow, opencv, imagesharp-head, fast-png-head, pillow-head, opencv-head matches the reference; color under alpha 0 zeroed4: wuffs, pngjs, wuffs-head, pngjs-head matches the reference; color under alpha 0 zeroed; 16→8 high byte2: chunky_png, chunky_png-head matches the reference; color under alpha 0 preserved; 16→8 high byte2: upng, upng-head	✓	✓	✓	✓	✓	≠	✓	✓	✓	✓	✓	✓	✓	≠	✓	✓	✓	✓	✓	≠	≠	≠	≠	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	≠	✓
y_trns-rgb8-blackpng IHDRtRNSIDATIEND tRNS names black (0, 0, 0), a color of the picture: those pixels have alpha 0. expected: display, conforms spec: §11.3.1.1 expected42 match 2 of 195 pixels differ2: fast-png, fast-png-head	✓	✓	✓	✓	✓	≠	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	M	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓
y_trns-rgb8-whitepng IHDRtRNSIDATIEND tRNS names white (255, 255, 255), a color of the picture: those pixels have alpha 0. expected: display, conforms spec: §11.3.1.1 expected32 match matches the reference; color under alpha 0 zeroed6: wuffs, pngjs, chunky_png, wuffs-head, pngjs-head, chunky_png-head 1 of 195 pixels differ6: fast-png, pngtopam, graphicsmagick, graphicsmagick-head, fast-png-head, pngtopam-head	✓	✓	✓	✓	✓	≠	✓	✓	✓	≠	≠	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	≠	M	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓
y_trns-rgb8-midpng IHDRtRNSIDATIEND tRNS names mid (13, 31, 128), a color of the picture: those pixels have alpha 0. expected: display, conforms spec: §11.3.1.1 expected32 match matches the reference; color under alpha 0 zeroed6: wuffs, pngjs, chunky_png, wuffs-head, pngjs-head, chunky_png-head 13 of 195 pixels differ6: fast-png, pngtopam, graphicsmagick, graphicsmagick-head, fast-png-head, pngtopam-head	✓	✓	✓	✓	✓	≠	✓	✓	✓	≠	≠	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	≠	M	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓
y_trns-rgb16-blackpng IHDRtRNSIDATIEND tRNS names black (0, 0, 0), a color of the picture: those pixels have alpha 0. expected: display, conforms spec: §11.3.1.1 expected36 match matches the reference; 16→8 high byte6: upng, pillow, chunky_png, upng-head, pillow-head, chunky_png-head 2 of 195 pixels differ2: fast-png, fast-png-head	✓	✓	✓	✓	✓	≠	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	M	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓
y_trns-rgb16-whitepng IHDRtRNSIDATIEND tRNS names white (65535, 65535, 65535), a color of the picture: those pixels have alpha 0. expected: display, conforms spec: §11.3.1.1 expected30 match matches the reference; color under alpha 0 preserved; 16→8 high byte4: upng, pillow, upng-head, pillow-head 1 of 195 pixels differ4: fast-png, pngtopam, fast-png-head, pngtopam-head matches the reference; color under alpha 0 zeroed4: wuffs, pngjs, wuffs-head, pngjs-head matches the reference; color under alpha 0 zeroed; 16→8 high byte2: chunky_png, chunky_png-head	✓	✓	✓	✓	✓	≠	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	≠	M	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓
y_trns-rgb16-midpng IHDRtRNSIDATIEND tRNS names mid (3277, 7864, 32768), a color of the picture: those pixels have alpha 0. expected: display, conforms spec: §11.3.1.1 expected27 match 13 of 195 pixels differ7: zune-png, imagesharp, fast-png, pngtopam, imagesharp-head, fast-png-head, pngtopam-head matches the reference; color under alpha 0 zeroed4: wuffs, pngjs, wuffs-head, pngjs-head matches the reference; color under alpha 0 zeroed; 16→8 high byte2: chunky_png, chunky_png-head matches the reference; color under alpha 0 preserved; 16→8 high byte2: upng, upng-head 192 of 195 pixels differ2: pillow, pillow-head	✓	✓	✓	✓	✓	≠	✓	✓	✓	✓	✓	✓	✓	≠	✓	✓	✓	✓	✓	✓	✓	≠	≠	✓	✓	≠	M	✓	✓	✓	✓	✓	✓	✓	✓	≠	✓
y_trns-g16-high-byte-onlypng IHDRtRNSIDATIEND tRNS (38144) equals no pixel but shares its high bytes with 18: a decoder comparing after reducing to 8 bits makes those transparent; nothing is. §15.3.3 says a decoder compares both bytes of a 16-bit tRNS value. expected: display, conforms spec: §11.3.1.1 expected40 match 192 of 195 pixels differ2: chunky_png, chunky_png-head matches the reference; 16→8 high byte2: upng, upng-head	✓	✓	✓	✓	≠	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓
y_trns-rgb16-high-byte-onlypng IHDRtRNSIDATIEND tRNS (3072, 7680, 32768) equals no pixel but shares its high bytes with 13: a decoder comparing after reducing to 8 bits makes those transparent; nothing is. §15.3.3 says a decoder compares both bytes of a 16-bit tRNS value. expected: display, conforms spec: §11.3.1.1 expected38 match 192 of 195 pixels differ2: chunky_png, chunky_png-head 194 of 195 pixels differ2: pillow, pillow-head matches the reference; 16→8 high byte2: upng, upng-head	✓	✓	✓	✓	≠	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	≠	≠	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓
y_pal8-trns-entry0png IHDRPLTEtRNSIDATIEND p8, tRNS of one byte 0: only entry 0 transparent. expected: display, conforms spec: §11.3.1.1 expected44 match	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓
y_pal1-trns-entry1png IHDRPLTEtRNSIDATIEND p1, tRNS ff 00: entry 1 transparent. expected: display, conforms spec: §11.3.1.1 expected44 match	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓
y_pal2-trns-entry3png IHDRPLTEtRNSIDATIEND p2, tRNS ff ff ff 00: entry 3 transparent. expected: display, conforms spec: §11.3.1.1 expected44 match	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓
i_iend-missingpng IHDRIDAT datastream ends after the last IDAT. §11.2 says a datastream ends with IEND; §13.1 lets a decoder treat the missing one as fatal, or not. expected: may-reject, does not conform expected14 match	✓	✓	R	R	R	R	✓	✓	R	R	R	R	R	✓	✓	R	R	✓	R	R	R	✓	✓	R	R	R	R	R	R	R	R	R	R	✓	✓	R	R
r_iend-len-4png IHDRIDATIEND IEND with four data bytes. §11.2.4 says IEND is the last chunk, therefore a decoder may ignore anything past it. expected: recover, does not conform spec: §15.3.1, §13.1, §13.3 expected38 match	✓	✓	R	R	R	R	✓	✓	R	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓
r_iend-duppng IHDRIDATIENDIEND two IEND chunks. §11.2.4 says IEND is the last chunk, therefore a decoder may ignore anything past it. expected: recover, does not conform spec: §15.3.1, §13.1, §13.3 expected42 match	✓	✓	R	R	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	R	R	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓
i_iend-crc-badpng IHDRIDATIEND IEND with a wrong CRC. §13.1 says a CRC mismatch may be fatal; a decoder that carries on uses the chunk as stored. expected: may-reject, does not conform spec: §5.5 expected35 match	✓	✓	R	R	R	✓	✓	✓	R	✓	✓	✓	✓	✓	✓	✓	✓	✓	R	✓	✓	✓	✓	R	R	✓	✓	R	✓	✓	✓	✓	✓	✓	✓	✓	✓
n_iend-before-idatpng IHDRIENDIDAT IEND before IDAT. §11.2 says that's a fatal error. expected: must-reject, does not conform no reference pixels1: java-imageio	R	R	R	R	R	R	R	R	R	R	R	R	R	R	A	R	R	R	R	R	R	R	R	R	R	R	R	R	R	R	R	R	R	R	R	R	R
r_trailing-garbagepng IHDRIDATIENDAGEG 56 bytes of non-chunk data after IEND. §11.2.4 says IEND is the last chunk, therefore a decoder may ignore anything past it. expected: recover, does not conform spec: §15.3.1, §13.1, §13.3 expected42 match	✓	✓	R	R	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	R	R	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓
r_trailing-partial-chunkpng IHDRIDATIENDtEXt a truncated chunk header after IEND. §11.2.4 says IEND is the last chunk, therefore a decoder may ignore anything past it. expected: recover, does not conform spec: §15.3.1, §13.1, §13.3 expected42 match	✓	✓	R	R	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	R	R	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓
n_chunk-unknown-critical-before-idatpng IHDRCrITIDATIEND unknown critical chunk CrIT before IDAT. §5.4 says a decoder that meets an unknown critical chunk must tell the user it can't safely interpret the image. expected: must-reject, does not conform spec: §13.1, §13.5 expected17 match	R	R	R	R	A^k	A^k	A^k	A^k	A^k	R	R	R	R	A^k	A^k	R	R	R	R	R	R	A^k	A^k	R	R	R	R	A^k	A^k	R	R	R	A^k	A^k	R	R	R
n_chunk-unknown-critical-after-idatpng IHDRIDATCrITIEND unknown critical chunk CrIT after IDAT. §5.4 says a decoder that meets an unknown critical chunk must tell the user it can't safely interpret the image. expected: must-reject, does not conform spec: §13.1, §13.5 expected24 match	R	R	R	R	A^k	A^k	A^k	A^k	A^k	R	R	R	R	A^k	A^k	R	R	A^k	R	R	R	A^k	A^k	R	R	R	R	A^k	A^k	A^k	A^k	R	A^k	A^k	A^k	R	A^k
y_chunk-unknown-ancillary-publicpng IHDRaBCDIDATIEND unknown ancillary public chunk. §5.7.2 reserves public chunk names for the W3C, so the file doesn't conform; a decoder still treats the chunk as unknown and shows the image. expected: display, does not conform spec: §5.4, §15.3.1 expected44 match	✓	✓	R	R	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓
y_chunk-unknown-ancillary-privatepng IHDRprIvIDATIEND unknown ancillary private chunk. §5.4 says an unknown ancillary chunk is never an error; a decoder just skips it. expected: display, conforms spec: §13.1 expected44 match	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓
y_chunk-unknown-ancillary-after-idatpng IHDRIDATprIvIEND unknown ancillary private chunk between IDAT and IEND. §5.4 says an unknown ancillary chunk is never an error; a decoder just skips it. expected: display, conforms spec: §13.1 expected44 match	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓
y_chunk-reserved-bit-ancillarypng IHDRtestIDATIEND reserved bit set on an unknown ancillary private chunk (test). Table 6 in §5.4 says a chunk with the reserved bit set makes the file non-conforming; a decoder still treats the chunk as unknown and shows the image. expected: display, does not conform spec: Table 6 expected31 match	✓	✓	R	R	✓	✓	✓	✓	✓	R	R	R	R	✓	✓	R	R	✓	R	R	R	✓	✓	✓	✓	R	R	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓
y_chunk-reserved-bit-knownpng IHDRgAmaIDATIEND gAma: a known name with the reserved bit set is a different, unknown chunk. Table 6 in §5.4 says a chunk with the reserved bit set makes the file non-conforming; a decoder still treats the chunk as unknown and shows the image. expected: display, does not conform spec: Table 6 expected31 match	✓	✓	R	R	✓	✓	✓	✓	✓	R	R	R	R	✓	✓	R	R	✓	R	R	R	✓	✓	✓	✓	R	R	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓
n_chunk-reserved-bit-criticalpng IHDRTestIDATIEND reserved bit set on an unknown critical private chunk (Test): still an unknown critical chunk. §5.4 says a decoder that meets an unknown critical chunk must tell the user it can't safely interpret the image. Table 6 in §5.4 says a chunk with the reserved bit set makes the file non-conforming; a decoder still treats the chunk as unknown and shows the image. expected: must-reject, does not conform spec: §13.1, §13.5, Table 6 expected17 match	R	R	R	R	A^k	A^k	A^k	A^k	A^k	R	R	R	R	A^k	A^k	R	R	R	R	R	R	A^k	A^k	R	R	R	R	A^k	A^k	R	R	R	A^k	A^k	R	R	R
i_chunk-type-digitpng IHDRt3XtIDATIEND chunk type containing a digit. §5.3 restricts chunk type bytes to letters; §13.2 lets a decoder check that and reject the file, or skip the chunk. expected: may-reject, does not conform expected28 match	✓	✓	R	R	✓	✓	✓	✓	✓	R	R	R	R	✓	✓	R	R	✓	R	R	R	✓	✓	✓	R	R	R	R	R	✓	✓	✓	✓	✓	✓	✓	✓
i_chunk-type-nulpng IHDRteX\x00IDATIEND chunk type containing a NUL byte. §5.3 restricts chunk type bytes to letters; §13.2 lets a decoder check that and reject the file, or skip the chunk. expected: may-reject, does not conform expected26 match	✓	✓	R	R	✓	✓	✓	✓	✓	R	R	R	R	✓	✓	R	R	✓	R	R	R	R	R	✓	R	R	R	R	R	✓	✓	✓	✓	✓	✓	✓	✓
i_chunk-type-spacepng IHDRteX IDATIEND chunk type containing a space. §5.3 restricts chunk type bytes to letters; §13.2 lets a decoder check that and reject the file, or skip the chunk. expected: may-reject, does not conform expected26 match	✓	✓	R	R	✓	✓	✓	✓	✓	R	R	R	R	✓	✓	R	R	✓	R	R	R	R	R	✓	R	R	R	R	R	✓	✓	✓	✓	✓	✓	✓	✓
n_chunk-len-2-31png IHDRtEXt ancillary chunk declaring length 2^31. §5.3 says a chunk length never exceeds 2^31−1, so that's a fatal error. expected: must-reject, does not conform	R	R	R	R	∞	R	R	R	R	R	R	R	R	R	R	R	R	R	R	R	R	R	R	R	R	R	R	R	R	R	R	R	∞	∞	R	R	R
n_chunk-len-huge-beyond-filepng IHDRtEXt ancillary chunk declaring 2^30 - 1 bytes in a file of a few hundred: a decoder that allocates the declared length first needs a gigabyte. §11.2 says that's a fatal error. expected: must-reject, does not conform	R	R	R	R	R	R	R	R	R	R	R	R	R	R	R	R	R	R	R	R	R	R	R	R	R	R	R	R	R	R	R	R	∞	∞	R	R	R
n_chunk-len-beyond-filepng IHDRtEXt ancillary chunk declaring more bytes than the file has. §11.2 says that's a fatal error. expected: must-reject, does not conform	R	R	R	R	R	R	R	R	R	R	R	R	R	R	R	R	R	R	R	R	R	R	R	R	R	R	R	R	R	R	R	R	R	R	R	R	R
i_chunk-ancillary-crc-badpng IHDRtEXtIDATIEND bad CRC on a tEXt chunk. §13.1 says a CRC mismatch may be fatal; a decoder that carries on may drop the chunk or use it as stored. expected: may-reject, does not conform spec: §5.5 expected35 match	✓	✓	R	R	R	✓	✓	✓	R	✓	✓	✓	✓	✓	✓	✓	✓	✓	R	✓	✓	R	R	✓	✓	✓	✓	R	✓	✓	✓	✓	✓	✓	✓	✓	✓
i_chunk-unknown-ancillary-crc-badpng IHDRprIvIDATIEND bad CRC on an unknown ancillary private chunk. §13.1 says a CRC mismatch may be fatal; a decoder that carries on may drop the chunk or use it as stored. expected: may-reject, does not conform spec: §5.5 expected37 match	✓	✓	R	R	R	✓	✓	✓	R	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	R	R	✓	✓	✓	✓	R	✓	✓	✓	✓	✓	✓	✓	✓	✓
i_chunk-gama-crc-badpng IHDRgAMAIDATIEND bad CRC on gAMA. §13.1 says a CRC mismatch may be fatal; a decoder that carries on may drop the chunk or use it as stored. expected: may-reject, does not conform spec: §5.5 expected33 match	✓	✓	R	R	R	✓	✓	✓	R	✓	✓	✓	✓	✓	✓	✓	✓	✓	R	✓	✓	R	R	R	R	✓	✓	R	✓	✓	✓	✓	✓	✓	✓	✓	✓
i_chunk-trns-crc-badpng IHDRtRNSIDATIEND bad CRC on a tRNS naming gray 149, a color of the picture: dropped, it stays opaque; used, it turns transparent. §13.1 says a CRC mismatch may be fatal; a decoder that carries on may drop the chunk or use it as stored. expected: may-reject, does not conform spec: §5.5 expected17 match matches crc:ignored (arguable: a chunk with a bad CRC used as stored); color under alpha 0 preserved14: stb_image, ffmpeg, zune-png, java-imageio, imagesharp, upng, graphicsmagick, stb_image-head, ffmpeg-head, graphicsmagick-head, zune-png-head, imagesharp-head, upng-head, pypng-head matches crc:ignored (arguable: a chunk with a bad CRC used as stored); color under alpha 0 zeroed2: wuffs, wuffs-head	✓	✓	R	R	R	✓	✓^c	✓^c	R	✓^c	✓^c	✓	✓	✓^c	✓^c	✓	✓	✓	R	✓	✓	R	R	R	R	✓	✓	R	✓^c	✓	✓	✓^c	✓^c	✓^c	✓^c	✓^c	✓^c
i_chunk-idat-crc-bad-firstpng IHDRIDATIDATIEND bad CRC on the first of two IDATs, data intact. §13.1 says a CRC mismatch may be fatal; a decoder that carries on uses the chunk as stored. expected: may-reject, does not conform spec: §5.5 expected20 match	✓^c	✓^c	R	R	R	✓^c	✓^c	✓^c	R	✓^c	✓^c	R	R	R	✓^c	R	R	R	R	R	R	✓^c	✓^c	R	R	R	R	R	✓^c	R	R	✓^c	✓^c	✓^c	✓^c	✓^c	✓^c
y_chunk-many-ancillarypng IHDRtEXt ×2000IDATIEND 2000 tEXt chunks before IDAT. expected: display, conforms spec: §11.3.3.2 expected42 match	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	R	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓
n_filter-type-5-first-rowpng IHDRIDATIEND filter type 5 on the first scanline. §9.2 defines exactly five filter types; §13.1 calls any other value a syntax error, which is fatal in image data. expected: must-reject, does not conform no reference pixels2: ffmpeg, ffmpeg-head no reference pixels1: upng the invalid byte taken as filter None (0) or Up (2)1: upng-head	R	R	R	R	R	R	A	A	R	R	R	R	R	R	R	R	R	R	R	R	R	R	R	R	R	R	R	R	R	R	R	R	A	A	R	R	R
n_filter-type-5-last-rowpng IHDRIDATIEND filter type 5 on the last scanline only. §9.2 defines exactly five filter types; §13.1 calls any other value a syntax error, which is fatal in image data. expected: must-reject, does not conform no reference pixels2: ffmpeg, ffmpeg-head the invalid byte taken as filter Paeth (4)1: upng-head no reference pixels1: upng	R	R	R	R	R	R	A	A	R	R	R	R	R	R	R	R	R	R	R	R	R	R	R	R	R	R	R	R	R	R	R	R	A	A	R	R	R
n_filter-type-255png IHDRIDATIEND filter type 255 on the first scanline. §9.2 defines exactly five filter types; §13.1 calls any other value a syntax error, which is fatal in image data. expected: must-reject, does not conform no reference pixels2: ffmpeg, ffmpeg-head no reference pixels1: upng the invalid byte taken as filter None (0) or Up (2)1: upng-head	R	R	R	R	R	R	A	A	R	R	R	R	R	R	R	R	R	R	R	R	R	R	R	R	R	R	R	R	R	R	R	R	A	A	R	R	R
n_filter-type-8png IHDRIDATIEND filter type 8 on the first scanline. §9.2 defines exactly five filter types; §13.1 calls any other value a syntax error, which is fatal in image data. expected: must-reject, does not conform no reference pixels2: ffmpeg, ffmpeg-head no reference pixels1: upng the invalid byte taken as filter None (0) or Up (2)1: upng-head	R	R	R	R	R	R	A	A	R	R	R	R	R	R	R	R	R	R	R	R	R	R	R	R	R	R	R	R	R	R	R	R	A	A	R	R	R
r_gama-len-2png IHDRgAMAIDATIEND gAMA with 2 bytes. §13.2 says a decoder can handle a wrong length on an ancillary chunk by ignoring the chunk. expected: recover, does not conform expected34 match	✓	✓	R	R	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	R	✓	✓	R	R	R	R	✓	✓	R	R	✓	✓	✓	✓	✓	✓	R	R
r_gama-len-0png IHDRgAMAIDATIEND gAMA with 0 bytes. §13.2 says a decoder can handle a wrong length on an ancillary chunk by ignoring the chunk. expected: recover, does not conform expected34 match	✓	✓	R	R	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	R	✓	✓	R	R	R	R	✓	✓	R	R	✓	✓	✓	✓	✓	✓	R	R
r_bkgd-len-0png IHDRbKGDIDATIEND bKGD with 0 bytes. §13.2 says a decoder can handle a wrong length on an ancillary chunk by ignoring the chunk. expected: recover, does not conform expected38 match	✓	✓	R	R	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	R	R	R	✓	✓	✓	✓	✓	✓	R	R	✓	✓	✓	✓	✓	✓	✓	✓
r_chrm-len-0png IHDRcHRMIDATIEND cHRM with 0 bytes. §13.2 says a decoder can handle a wrong length on an ancillary chunk by ignoring the chunk. expected: recover, does not conform expected39 match	✓	✓	R	R	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	R	✓	✓	R	R	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	R
r_phys-len-0png IHDRpHYsIDATIEND pHYs with 0 bytes. §13.2 says a decoder can handle a wrong length on an ancillary chunk by ignoring the chunk. expected: recover, does not conform expected33 match	✓	✓	R	R	✓	R	✓	✓	✓	✓	✓	✓	✓	R	✓	✓	✓	✓	R	✓	✓	R	R	✓	✓	✓	✓	R	R	✓	✓	✓	✓	✓	✓	✓	R
r_sbit-len-0png IHDRsBITIDATIEND sBIT with 0 bytes. §13.2 says a decoder can handle a wrong length on an ancillary chunk by ignoring the chunk. expected: recover, does not conform expected39 match	✓	✓	R	R	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	R	✓	✓	✓	✓	✓	✓	✓	✓	R	R	✓	✓	✓	✓	✓	✓	✓	R
r_srgb-len-0png IHDRsRGBIDATIEND sRGB with 0 bytes. §13.2 says a decoder can handle a wrong length on an ancillary chunk by ignoring the chunk. expected: recover, does not conform expected40 match	✓	✓	R	R	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	R	✓	✓	R	R	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓
r_time-len-0png IHDRtIMEIDATIEND tIME with 0 bytes. §13.2 says a decoder can handle a wrong length on an ancillary chunk by ignoring the chunk. expected: recover, does not conform expected42 match	✓	✓	R	R	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	R	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓
r_cicp-len-0png IHDRcICPIDATIEND cICP with 0 bytes. §13.2 says a decoder can handle a wrong length on an ancillary chunk by ignoring the chunk. expected: recover, does not conform expected39 match	✓	✓	R	R	✓	✓	R	R	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	R	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	R
r_mdcv-len-0png IHDRcICPmDCVIDATIEND mDCV with 0 bytes, with the cICP it must accompany. §13.2 says a decoder can handle a wrong length on an ancillary chunk by ignoring the chunk. expected: recover, does not conform expected42 match	✓	✓	R	R	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	R	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓
r_clli-len-0png IHDRcLLIIDATIEND cLLI with 0 bytes. §13.2 says a decoder can handle a wrong length on an ancillary chunk by ignoring the chunk. expected: recover, does not conform expected41 match	✓	✓	R	R	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	R	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	R
r_iccp-len-0png IHDRiCCPIDATIEND iCCP with 0 bytes. §11.3.2.3 lays out iCCP as name, null, method, profile; a decoder should ignore one that doesn't fit. expected: recover, does not conform expected37 match	✓	✓	R	R	✓	R	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	R	✓	✓	R	R	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	R	✓	✓	✓
r_itxt-len-0png IHDRiTXtIDATIEND iTXt with 0 bytes. §11.3.3.4 lays out iTXt with three null separators; a decoder should ignore one that doesn't fit. expected: recover, does not conform expected40 match	✓	✓	R	R	R	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	R	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓
r_ztxt-len-0png IHDRzTXtIDATIEND zTXt with 0 bytes. §11.3.3.3 lays out zTXt as keyword, null, method, compressed text; a decoder should ignore one that doesn't fit. expected: recover, does not conform expected39 match	✓	✓	R	R	R	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	R	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	R	✓	✓	✓
r_splt-len-0png IHDRsPLTIDATIEND sPLT with 0 bytes. §11.3.4.4 lays out sPLT as name, null, depth, entries; a decoder should ignore one that doesn't fit. expected: recover, does not conform expected44 match	✓	✓	R	R	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓
r_hist-len-0png IHDRPLTEhISTIDATIEND hIST with 0 bytes. §11.3.4.2 says hIST has one entry per palette entry; a decoder should ignore the chunk otherwise. expected: recover, does not conform expected44 match	✓	✓	R	R	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓
r_actl-len-0png IHDRacTLIDATIEND acTL with 0 bytes. §11.3.6.1 says acTL is 8 bytes; a decoder should ignore it otherwise and show the static image. expected: recover, does not conform spec: §13.2 expected33 match	✓	✓	R	R	✓	✓	✓	✓	✓	✓	✓	✓	✓	R	✓	✓	✓	✓	✓	R	R	R	R	✓	✓	✓	✓	✓	✓	✓	✓	✓	R	R	R	R	✓
r_gama-len-5png IHDRgAMAIDATIEND gAMA with 5 bytes. §13.2 says a decoder can handle a wrong length on an ancillary chunk by ignoring the chunk. expected: recover, does not conform expected38 match	✓	✓	R	R	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	R	✓	✓	✓	✓	✓	✓	✓	✓	R	R	✓	✓	✓	✓	✓	✓	R	R
r_gama-value-0png IHDRgAMAIDATIEND gAMA 0 (a meaningless value). §13.13 says a gAMA of zero is meaningless and a decoder should ignore it. expected: recover, does not conform expected44 match	✓	✓	R	R	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓
r_gama-value-hugepng IHDRgAMAIDATIEND gAMA 4294967295 (gamma 42949.67). §7.1 limits four-byte integers to 2^31−1; a decoder should ignore an ancillary chunk that breaks that. expected: recover, does not conform expected44 match	✓	✓	A	A	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓
r_gama-after-pltepng IHDRPLTEgAMAIDATIEND gAMA after PLTE. Table 7 in §5.6 puts this chunk before PLTE and IDAT; §13.2 says a decoder should ignore a misplaced one. expected: recover, does not conform spec: Table 7 expected44 match	✓	✓	R	R	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓
r_gama-after-idatpng IHDRIDATgAMAIEND gAMA after IDAT. Table 7 in §5.6 puts this chunk before PLTE and IDAT; §13.2 says a decoder should ignore a misplaced one. expected: recover, does not conform spec: Table 7 expected44 match	✓	✓	R	R	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓
r_gama-duppng IHDRgAMA ×2IDATIEND two gAMA chunks. Table 7 in §5.6 allows this chunk once; a decoder should ignore the second. expected: recover, does not conform spec: Table 7, §13.1 expected44 match	✓	✓	R	R	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓
r_srgb-len-2png IHDRsRGBIDATIEND sRGB with 2 bytes. §13.2 says a decoder can handle a wrong length on an ancillary chunk by ignoring the chunk. expected: recover, does not conform expected42 match	✓	✓	R	R	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	R	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓
r_srgb-intent-4png IHDRsRGBIDATIEND sRGB rendering intent 4 (defined: 0-3). §11.3.2.5 allows rendering intents 0 to 3; a decoder should ignore the chunk otherwise. expected: recover, does not conform expected44 match	✓	✓	R	R	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓
r_srgb-after-idatpng IHDRIDATsRGBIEND sRGB after IDAT. Table 7 in §5.6 puts this chunk before PLTE and IDAT; §13.2 says a decoder should ignore a misplaced one. expected: recover, does not conform spec: Table 7 expected44 match	✓	✓	R	R	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓
r_srgb-and-iccppng IHDRsRGBiCCPIDATIEND sRGB and iCCP both present. §5.6 says iCCP and sRGB should not both be present. expected: recover, does not conform spec: Table 7 expected44 match	✓	✓	R	R	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓
r_srgb-gama-mismatchpng IHDRsRGBgAMAIDATIEND sRGB with gAMA 100000, not the 45455 sRGB implies. §11.3.2.5 says a gAMA or cHRM next to sRGB carries only the values of Table 17; a decoder that uses sRGB ignores both anyway. expected: recover, does not conform spec: 2nd ed. §11.3.3.5 expected44 match	✓	✓	A	A	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓
r_srgb-chrm-mismatchpng IHDRsRGBcHRMIDATIEND sRGB with a cHRM whose last value is 6001, not the 6000 sRGB implies. §11.3.2.5 says a gAMA or cHRM next to sRGB carries only the values of Table 17; a decoder that uses sRGB ignores both anyway. expected: recover, does not conform spec: 2nd ed. §11.3.3.5 expected44 match	✓	✓	A	A	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓
r_chrm-len-30png IHDRcHRMIDATIEND cHRM with 30 bytes. §13.2 says a decoder can handle a wrong length on an ancillary chunk by ignoring the chunk. expected: recover, does not conform expected39 match	✓	✓	R	R	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	R	✓	✓	R	R	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	R
y_chrm-all-zeropng IHDRcHRMIDATIEND cHRM with every value 0 (degenerate). expected: display, conforms spec: §11.3.2.1 expected44 match	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓
r_chrm-after-pltepng IHDRPLTEcHRMIDATIEND cHRM after PLTE. Table 7 in §5.6 puts this chunk before PLTE and IDAT; §13.2 says a decoder should ignore a misplaced one. expected: recover, does not conform spec: Table 7 expected44 match	✓	✓	R	R	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓
r_phys-len-8png IHDRpHYsIDATIEND pHYs with 8 bytes. §13.2 says a decoder can handle a wrong length on an ancillary chunk by ignoring the chunk. expected: recover, does not conform expected33 match	✓	✓	R	R	✓	R	✓	✓	✓	✓	✓	✓	✓	R	✓	✓	✓	✓	R	✓	✓	R	R	✓	✓	✓	✓	R	R	✓	✓	✓	✓	✓	✓	✓	R
r_phys-unit-2png IHDRpHYsIDATIEND pHYs unit specifier 2 (defined: 0, 1). §11.3.4.3 defines units 0 and 1; a decoder should ignore the chunk otherwise. expected: recover, does not conform expected44 match	✓	✓	R	R	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓
y_phys-zeropng IHDRpHYsIDATIEND pHYs 0 pixels per metre. expected: display, conforms spec: §11.3.4.3 expected44 match	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓
r_phys-after-idatpng IHDRIDATpHYsIEND pHYs after IDAT. Table 7 in §5.6 puts this chunk before IDAT; a decoder should ignore a misplaced one. expected: recover, does not conform spec: Table 7 expected42 match	✓	✓	R	R	✓	✓	R	R	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓
r_time-len-6png IHDRtIMEIDATIEND tIME with 6 bytes. §13.2 says a decoder can handle a wrong length on an ancillary chunk by ignoring the chunk. expected: recover, does not conform expected42 match	✓	✓	R	R	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	R	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓
r_time-month-13png IHDRtIMEIDATIEND tIME month 13. §11.3.5.1 gives each tIME field a range; a decoder should ignore the chunk otherwise. expected: recover, does not conform expected44 match	✓	✓	R	R	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓
r_time-day-0png IHDRtIMEIDATIEND tIME day 0. §11.3.5.1 gives each tIME field a range; a decoder should ignore the chunk otherwise. expected: recover, does not conform expected44 match	✓	✓	R	R	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓
y_time-second-60png IHDRtIMEIDATIEND tIME second 60 (allowed for leap seconds). expected: display, conforms spec: §11.3.5.1 expected44 match	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓
y_time-year-0png IHDRtIMEIDATIEND tIME year 0. expected: display, conforms spec: §11.3.5.1 expected44 match	✓	✓	R	R	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓
r_time-duppng IHDRtIME ×2IDATIEND two tIME chunks. Table 7 in §5.6 allows this chunk once; a decoder should ignore the second. expected: recover, does not conform spec: Table 7, §13.1 expected44 match	✓	✓	R	R	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓
r_text-no-nullpng IHDRtEXtIDATIEND tEXt without a null separator. §11.3.3.2 says a null byte separates keyword and text; a decoder should ignore a chunk without one. expected: recover, does not conform expected42 match	✓	✓	A	A	✓	R	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓
r_text-empty-keywordpng IHDRtEXtIDATIEND tEXt with an empty keyword. §11.3.3.1 says a keyword is 1 to 79 bytes; a decoder should ignore the chunk otherwise. expected: recover, does not conform spec: §11.3.2.3, §11.3.4.4 expected40 match	✓	✓	R	R	✓	R	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	R	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓
r_text-keyword-80png IHDRtEXtIDATIEND tEXt keyword of 80 characters (limit 79). §11.3.3.1 says a keyword is 1 to 79 bytes; a decoder should ignore the chunk otherwise. expected: recover, does not conform spec: §11.3.2.3, §11.3.4.4 expected40 match	✓	✓	R	R	✓	R	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	R	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓
r_text-len-0png IHDRtEXtIDATIEND zero-length tEXt. §11.3.3.2 says a null byte separates keyword and text; a decoder should ignore a chunk without one. expected: recover, does not conform expected40 match	✓	✓	R	R	✓	R	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	R	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓
r_text-keyword-spacespng IHDRtEXtIDATIEND tEXt keyword with leading and trailing spaces. §11.3.3.1 forbids leading, trailing and consecutive spaces in a keyword; a decoder should ignore the chunk otherwise. expected: recover, does not conform spec: §11.3.2.3, §11.3.4.4 expected44 match	✓	✓	R	R	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓
r_text-control-charpng IHDRtEXtIDATIEND tEXt whose text holds ESC, a C0 control. §11.3.3.1 restricts text to printable Latin-1 plus line feed; a decoder should ignore the chunk otherwise. expected: recover, does not conform expected44 match	✓	✓	A	A	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓
r_text-second-nullpng IHDRtEXtIDATIEND tEXt whose text holds a second NUL. §11.3.3.2 says neither keyword nor text may contain a null; a decoder should ignore the chunk otherwise. expected: recover, does not conform expected44 match	✓	✓	R	R	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓
r_text-non-latin1png IHDRtEXtIDATIEND tEXt with bytes that are not Latin-1 text. §11.3.3.1 restricts text to printable Latin-1 plus line feed; a decoder should ignore the chunk otherwise. expected: recover, does not conform expected44 match	✓	✓	A	A	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓
r_ztxt-method-1png IHDRzTXtIDATIEND zTXt compression method 1. §11.3.3.3 defines only compression method 0; a decoder should ignore the chunk otherwise. expected: recover, does not conform expected38 match	✓	✓	R	R	R	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	R	✓	✓	R	R	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓
r_ztxt-bad-zlibpng IHDRzTXtIDATIEND zTXt whose zlib stream is garbage. §11.3.3.3 says the text is a zlib stream; a decoder should ignore a chunk whose stream is broken. expected: recover, does not conform spec: §10.3 expected39 match	✓	✓	A	A	R	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	R	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	R	✓	✓	✓
r_ztxt-bad-adlerpng IHDRzTXtIDATIEND zTXt with a wrong Adler-32. §11.3.3.3 says the text is a zlib stream; a decoder should ignore a chunk whose stream is broken. expected: recover, does not conform spec: §10.3 expected40 match	✓	✓	A	A	R	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	R	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓
r_ztxt-no-nullpng IHDRzTXtIDATIEND zTXt without a null separator. §11.3.3.3 lays out zTXt as keyword, null, method, compressed text; a decoder should ignore one that doesn't fit. expected: recover, does not conform expected39 match	✓	✓	R	R	R	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	R	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	R	✓	✓	✓
r_ztxt-len-1png IHDRzTXtIDATIEND zTXt of one byte. §11.3.3.1 says a keyword is 1 to 79 bytes; a decoder should ignore the chunk otherwise. expected: recover, does not conform spec: §11.3.2.3, §11.3.4.4 expected37 match	✓	✓	R	R	R	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	R	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	R	✓	R	R
r_ztxt-bombpng IHDRzTXtIDATIEND zTXt that inflates to 64 MiB of zeros (so its text holds NULs). §11.3.3.3 says the decompressed text follows tEXt's rules, so no nulls; a decoder should ignore the chunk otherwise. expected: recover, does not conform spec: §11.3.3.2 expected39 match	✓	✓	A	A	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	R	✓	✓	R	R	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	∞	✓	✓	✓
r_itxt-flag-2png IHDRiTXtIDATIEND iTXt compression flag 2. §11.3.3.4 says the compression flag is 0 or 1; a decoder should ignore the chunk otherwise. expected: recover, does not conform expected39 match	✓	✓	R	R	R	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	R	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	R	✓	✓	✓
r_itxt-method-1png IHDRiTXtIDATIEND iTXt compressed with method 1. §11.3.3.4 defines only compression method 0 for compressed text; a decoder should ignore the chunk otherwise. expected: recover, does not conform expected40 match	✓	✓	R	R	R	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	R	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓
r_itxt-bad-zlibpng IHDRiTXtIDATIEND iTXt compressed flag set, garbage stream. §11.3.3.4 says compressed text is a zlib stream; a decoder should ignore a chunk whose stream is broken. expected: recover, does not conform spec: §10.3 expected39 match	✓	✓	A	A	R	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	R	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	R	✓	✓	✓
r_itxt-bad-adlerpng IHDRiTXtIDATIEND iTXt compressed, with a wrong Adler-32. §11.3.3.4 says compressed text is a zlib stream; a decoder should ignore a chunk whose stream is broken. expected: recover, does not conform spec: §10.3 expected40 match	✓	✓	A	A	R	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	R	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓
r_itxt-truncatedpng IHDRiTXtIDATIEND iTXt ending after the keyword. §11.3.3.4 lays out iTXt with three null separators; a decoder should ignore one that doesn't fit. expected: recover, does not conform expected35 match	✓	✓	R	R	R	✓	✓	✓	✓	✓	✓	✓	✓	R	✓	✓	✓	✓	R	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	R	✓	R	R
r_itxt-bad-utf8png IHDRiTXtIDATIEND iTXt whose text is not UTF-8. §11.3.3.4 says the translated keyword and text are UTF-8; a decoder should ignore the chunk otherwise. expected: recover, does not conform expected42 match	✓	✓	A	A	R	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓
r_itxt-language-numericpng IHDRiTXtIDATIEND iTXt with language tag 123, which is not a language tag. §11.3.3.4 says the language tag is a BCP 47 tag; a decoder should ignore the chunk otherwise. expected: recover, does not conform expected44 match	✓	✓	A	A	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓
r_sbit-len-wrongpng IHDRsBITIDATIEND sBIT with 3 bytes on grayscale (should be 1). §13.2 says a decoder can handle a wrong length on an ancillary chunk by ignoring the chunk. expected: recover, does not conform expected40 match	✓	✓	R	R	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	R	✓	✓	✓	✓	✓	✓	✓	✓	R	R	✓	✓	✓	✓	✓	✓	✓	✓
r_sbit-value-0png IHDRsBITIDATIEND sBIT 0. §11.3.2.4 says each sBIT depth is between 1 and the sample depth; a decoder should ignore the chunk otherwise. expected: recover, does not conform expected41 match	✓	✓	R	R	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	R	✓	✓	✓	✓	✓	✓	✓	✓	R	✓	✓	✓	✓	✓	✓	✓	✓	✓
r_sbit-value-9png IHDRsBITIDATIEND sBIT 9 on an 8-bit image. §11.3.2.4 says each sBIT depth is between 1 and the sample depth; a decoder should ignore the chunk otherwise. expected: recover, does not conform expected41 match	✓	✓	R	R	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	R	✓	✓	✓	✓	✓	✓	✓	✓	R	✓	✓	✓	✓	✓	✓	✓	✓	✓
r_sbit-after-pltepng IHDRPLTEsBITIDATIEND sBIT after PLTE. Table 7 in §5.6 puts this chunk before PLTE and IDAT; §13.2 says a decoder should ignore a misplaced one. expected: recover, does not conform spec: Table 7 expected44 match	✓	✓	R	R	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓
r_sbit-rgb16-17png IHDRsBITIDATIEND sBIT 17 on a 16-bit image. §11.3.2.4 says each sBIT depth is between 1 and the sample depth; a decoder should ignore the chunk otherwise. expected: recover, does not conform expected35 match matches the reference; 16→8 high byte6: upng, pillow, chunky_png, upng-head, pillow-head, chunky_png-head	✓	✓	R	R	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	R	✓	✓	✓	✓	✓	✓	✓	✓	R	✓	✓	✓	✓	✓	✓	✓	✓	✓
r_bkgd-len-wrong-graypng IHDRbKGDIDATIEND bKGD of 1 byte on grayscale (should be 2). §13.2 says a decoder can handle a wrong length on an ancillary chunk by ignoring the chunk. expected: recover, does not conform expected40 match	✓	✓	R	R	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	R	✓	✓	✓	✓	✓	✓	✓	✓	R	R	✓	✓	✓	✓	✓	✓	✓	✓
r_bkgd-len-wrong-rgbpng IHDRbKGDIDATIEND bKGD of 2 bytes on truecolor (should be 6). §13.2 says a decoder can handle a wrong length on an ancillary chunk by ignoring the chunk. expected: recover, does not conform expected40 match	✓	✓	R	R	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	R	✓	✓	✓	✓	✓	✓	✓	✓	R	R	✓	✓	✓	✓	✓	✓	✓	✓
r_bkgd-pal-index-beyondpng IHDRPLTEbKGDIDATIEND bKGD index 36 for a 36-entry palette. §11.3.4.1 says the bKGD value of an indexed image is a palette index; a decoder should ignore one past the palette. expected: recover, does not conform expected42 match	✓	✓	R	R	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	R	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓
r_bkgd-before-pltepng IHDRbKGDPLTEIDATIEND bKGD before PLTE. Table 7 in §5.6 puts this chunk after PLTE and before IDAT; a decoder should ignore a misplaced one. expected: recover, does not conform spec: Table 7 expected40 match	✓	✓	R	R	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	R	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	R	R	✓	✓	✓	✓	✓	✓
r_bkgd-after-idatpng IHDRIDATbKGDIEND bKGD after IDAT. Table 7 in §5.6 puts this chunk after PLTE and before IDAT; a decoder should ignore a misplaced one. expected: recover, does not conform spec: Table 7 expected44 match	✓	✓	R	R	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓
y_bkgd-gray-highbytepng IHDRbKGDIDATIEND bKGD 0x0180 on 8-bit grayscale. §11.3.4.1 says a decoder masks a bKGD value to the bit depth before using it. expected: display, conforms expected44 match	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓
r_bkgd-len-4png IHDRbKGDIDATIEND bKGD of 4 bytes on grayscale (no color type uses 4). §13.2 says a decoder can handle a wrong length on an ancillary chunk by ignoring the chunk. expected: recover, does not conform expected38 match	✓	✓	R	R	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	R	R	R	✓	✓	✓	✓	✓	✓	R	R	✓	✓	✓	✓	✓	✓	✓	✓
r_hist-len-wrongpng IHDRPLTEhISTIDATIEND hIST with 2 entries for a 36-entry palette. §11.3.4.2 says hIST has one entry per palette entry; a decoder should ignore the chunk otherwise. expected: recover, does not conform expected44 match	✓	✓	R	R	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓
r_hist-before-pltepng IHDRhISTPLTEIDATIEND hIST before PLTE. Table 7 in §5.6 puts this chunk after PLTE and before IDAT; a decoder should ignore a misplaced one. expected: recover, does not conform spec: Table 7 expected41 match	✓	✓	R	R	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	R	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	R	R	✓	✓	✓
r_hist-without-pltepng IHDRhISTIDATIEND hIST in an image with no palette. §11.3.4.2 says hIST has one entry per palette entry; a decoder should ignore the chunk otherwise. expected: recover, does not conform expected42 match	✓	✓	R	R	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	R	R	✓	✓	✓
r_splt-depth-7png IHDRsPLTIDATIEND sPLT sample depth 7 (defined: 8, 16). §11.3.4.4 says the sPLT sample depth is 8 or 16; a decoder should ignore the chunk otherwise. expected: recover, does not conform expected44 match	✓	✓	R	R	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓
r_splt-len-wrongpng IHDRsPLTIDATIEND sPLT whose entries are not a whole number of 6-byte records. §11.3.4.4 says sPLT entries are 6 or 10 bytes each; a decoder should ignore a chunk whose length doesn't divide. expected: recover, does not conform expected44 match	✓	✓	R	R	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓
r_splt-no-nullpng IHDRsPLTIDATIEND sPLT without a null separator. §11.3.4.4 lays out sPLT as name, null, depth, entries; a decoder should ignore one that doesn't fit. expected: recover, does not conform expected44 match	✓	✓	R	R	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓
r_splt-dup-namepng IHDRsPLT ×2IDATIEND two sPLT chunks with the same name. §11.3.4.4 says each sPLT has a different name; a decoder should ignore the later duplicate. expected: recover, does not conform expected44 match	✓	✓	A	A	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓
r_splt-after-idatpng IHDRIDATsPLTIEND sPLT after IDAT. Table 7 in §5.6 puts this chunk before IDAT; a decoder should ignore a misplaced one. expected: recover, does not conform spec: Table 7 expected44 match	✓	✓	R	R	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓
r_iccp-method-1png IHDRiCCPIDATIEND iCCP compression method 1. §11.3.2.3 defines only compression method 0; a decoder should ignore the chunk otherwise. expected: recover, does not conform expected36 match	✓	✓	R	R	✓	R	R	R	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	R	✓	✓	R	R	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓
r_iccp-name-emptypng IHDRiCCPIDATIEND iCCP with an empty profile name. §11.3.3.1 says a keyword is 1 to 79 bytes; a decoder should ignore the chunk otherwise. expected: recover, does not conform spec: §11.3.2.3, §11.3.4.4 expected40 match	✓	✓	R	R	✓	R	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	R	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓
r_iccp-name-80png IHDRiCCPIDATIEND iCCP profile name of 80 characters. §11.3.3.1 says a keyword is 1 to 79 bytes; a decoder should ignore the chunk otherwise. expected: recover, does not conform spec: §11.3.2.3, §11.3.4.4 expected38 match	✓	✓	R	R	✓	R	R	R	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	R	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓
r_iccp-no-nullpng IHDRiCCPIDATIEND iCCP without a null separator. §11.3.2.3 lays out iCCP as name, null, method, profile; a decoder should ignore one that doesn't fit. expected: recover, does not conform expected37 match	✓	✓	R	R	✓	R	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	R	✓	✓	R	R	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	R	✓	✓	✓
r_iccp-profile-emptypng IHDRiCCPIDATIEND iCCP whose profile decompresses to 0 bytes. §11.3.2.3 says the decompressed data is an ICC profile; a decoder should ignore one that isn't. expected: recover, does not conform expected42 match	✓	✓	A	A	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	R	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓
r_iccp-profile-garbagepng IHDRiCCPIDATIEND iCCP whose profile is not an ICC profile. §11.3.2.3 says the decompressed data is an ICC profile; a decoder should ignore one that isn't. expected: recover, does not conform expected44 match	✓	✓	A	A	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓
r_iccp-bad-zlib-headerpng IHDRiCCPIDATIEND iCCP whose zlib header is invalid. §11.3.2.3 says the profile is a zlib stream; a decoder should ignore a chunk whose stream is broken. expected: recover, does not conform spec: §10.3 expected38 match	✓	✓	A	A	✓	R	R	R	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	R	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓
r_iccp-bad-adlerpng IHDRiCCPIDATIEND iCCP with a wrong Adler-32. §11.3.2.3 says the profile is a zlib stream; a decoder should ignore a chunk whose stream is broken. expected: recover, does not conform spec: §10.3 expected40 match	✓	✓	A	A	✓	✓	R	R	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	R	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓
r_iccp-truncated-zlibpng IHDRiCCPIDATIEND iCCP whose zlib stream stops halfway. §11.3.2.3 says the profile is a zlib stream; a decoder should ignore a chunk whose stream is broken. expected: recover, does not conform spec: §10.3 expected40 match	✓	✓	A	A	✓	R	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	R	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓
r_iccp-after-pltepng IHDRPLTEiCCPIDATIEND iCCP after PLTE. Table 7 in §5.6 puts this chunk before PLTE and IDAT; §13.2 says a decoder should ignore a misplaced one. expected: recover, does not conform spec: Table 7 expected44 match	✓	✓	R	R	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓
r_iccp-duppng IHDRiCCP ×2IDATIEND two iCCP chunks. Table 7 in §5.6 allows this chunk once; a decoder should ignore the second. expected: recover, does not conform spec: Table 7, §13.1 expected44 match	✓	✓	R	R	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓
r_iccp-bombpng IHDRiCCPIDATIEND iCCP that inflates to 64 MiB. §11.3.2.3 says the decompressed data is an ICC profile; a decoder should ignore one that isn't. expected: recover, does not conform expected38 match	✓	✓	A	A	✓	✓	R	R	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	R	✓	✓	R	R	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓
r_exif-len-0png IHDReXIfIDATIEND zero-length eXIf. §11.3.4.5.2 says eXIf starts with a TIFF header and a decoder should check that; it should ignore the chunk otherwise. expected: recover, does not conform spec: §13.3, Extensions 1.5.0 §3.7.2 expected42 match	✓	✓	A	A	✓	✓	R	R	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓
r_exif-garbagepng IHDReXIfIDATIEND eXIf whose payload is not a TIFF header. §11.3.4.5.2 says eXIf starts with a TIFF header and a decoder should check that; it should ignore the chunk otherwise. expected: recover, does not conform spec: §13.3, Extensions 1.5.0 §3.7.2 expected42 match	✓	✓	A	A	✓	✓	R	R	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓
r_exif-tiff-header-onlypng IHDReXIfIDATIEND eXIf with a TIFF header and no IFD. §11.3.4.5 says eXIf holds an Exif profile in TIFF framing; a decoder should ignore one whose structure is broken. expected: recover, does not conform spec: Extensions 1.5.0 §3.7 expected42 match	✓	✓	A	A	✓	✓	R	R	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓
r_exif-bad-ifd-offsetpng IHDReXIfIDATIEND eXIf whose first IFD offset points far outside the chunk. §11.3.4.5 says eXIf holds an Exif profile in TIFF framing; a decoder should ignore one whose structure is broken. expected: recover, does not conform spec: Extensions 1.5.0 §3.7 expected42 match	✓	✓	A	A	✓	✓	R	R	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓
r_exif-after-idatpng IHDRIDATeXIfIEND eXIf after IDAT (table 7: before IDAT). Table 7 in §5.6 puts this chunk before IDAT; a decoder should ignore a misplaced one. expected: recover, does not conform spec: Table 7 expected44 match	✓	✓	R	R	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓
r_cicp-len-3png IHDRcICPIDATIEND cICP with 3 bytes. §13.2 says a decoder can handle a wrong length on an ancillary chunk by ignoring the chunk. expected: recover, does not conform expected41 match	✓	✓	R	R	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	R	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	R
r_cicp-primaries-200png IHDRcICPIDATIEND cICP color primaries 200, a code point H.273 reserves. §11.3.2.6 takes the color primaries from H.273, which reserves this value; §13.2 says a decoder can ignore the chunk. expected: recover, does not conform expected44 match	✓	✓	R	R	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓
r_cicp-transfer-200png IHDRcICPIDATIEND cICP transfer characteristics 200, a code point H.273 reserves. §11.3.2.6 takes the transfer function from H.273, which reserves this value; §13.2 says a decoder can ignore the chunk. expected: recover, does not conform expected44 match	✓	✓	R	R	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓
r_cicp-matrix-1png IHDRcICPIDATIEND cICP matrix coefficients 1 (PNG requires 0). §11.3.2.6 says the matrix coefficients are 0, since PNG is RGB only; a decoder should ignore the chunk otherwise. expected: recover, does not conform expected42 match	✓	✓	R	R	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	R	R	✓	✓	✓	✓	✓	✓
r_cicp-range-2png IHDRcICPIDATIEND cICP video full range flag 2. §11.3.2.6 says the full-range flag is 0 or 1; a decoder should ignore the chunk otherwise. expected: recover, does not conform expected42 match	✓	✓	R	R	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	R	R	✓	✓	✓	✓	✓	✓
r_cicp-after-pltepng IHDRPLTEcICPIDATIEND cICP after PLTE. Table 7 in §5.6 puts this chunk before PLTE and IDAT; §13.2 says a decoder should ignore a misplaced one. expected: recover, does not conform spec: Table 7 expected44 match	✓	✓	R	R	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓
r_mdcv-len-wrongpng IHDRcICPmDCVIDATIEND mDCV with 20 bytes (should be 24), with the cICP it must accompany. §13.2 says a decoder can handle a wrong length on an ancillary chunk by ignoring the chunk. expected: recover, does not conform expected42 match	✓	✓	R	R	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	R	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓
r_clli-len-wrongpng IHDRcLLIIDATIEND cLLI with 6 bytes (should be 8). §13.2 says a decoder can handle a wrong length on an ancillary chunk by ignoring the chunk. expected: recover, does not conform expected41 match	✓	✓	R	R	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	R	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	R
r_actl-len-7png IHDRacTLIDATIEND acTL with 7 bytes and no frame control chunks: a still image with a broken animation header. §11.3.6.1 says acTL is 8 bytes; a decoder should ignore it otherwise and show the static image. expected: recover, does not conform spec: §13.2 expected33 match	✓	✓	R	R	✓	✓	✓	✓	✓	✓	✓	✓	✓	R	✓	✓	✓	✓	✓	R	R	R	R	✓	✓	✓	✓	✓	✓	✓	✓	✓	R	R	R	R	✓
r_actl-frames-0png IHDRacTLIDATIEND acTL declaring 0 frames and no fcTL: the default image is all there is. §11.3.6.1 says 0 is not a valid frame count; §13.1 says a decoder should fall back to the static image. expected: recover, does not conform expected38 match	✓	✓	R	R	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	R	R	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	R	R	R	✓	✓
r_actl-after-idatpng IHDRIDATacTLIEND acTL after IDAT, no fcTL. §11.3.6.1 says acTL comes before IDAT; a decoder should ignore a late one and show the static image. expected: recover, does not conform spec: §5.6 expected42 match	✓	✓	R	R	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	R	R	✓	✓	✓
r_fctl-len-25png IHDRacTLfcTLIDATIEND fcTL of 25 bytes before IDAT. §11.3.6.2 says fcTL is 26 bytes; a decoder should ignore it otherwise and show the static image. expected: recover, does not conform spec: §13.2 expected28 match 195 of 195 pixels differ1: upng-head	✓	✓	R	R	✓	✓	R	R	✓	✓	✓	✓	✓	R	✓	✓	✓	✓	✓	R	R	R	R	✓	✓	✓	✓	✓	✓	R	R	✓	!	≠	R	R	R
r_fctl-len-0png IHDRacTLfcTLIDATIEND fcTL of 0 bytes before IDAT. §11.3.6.2 says fcTL is 26 bytes; a decoder should ignore it otherwise and show the static image. expected: recover, does not conform spec: §13.2 expected27 match	✓	✓	R	R	✓	✓	R	R	✓	✓	✓	✓	✓	R	✓	✓	R	✓	✓	R	R	R	R	✓	✓	✓	✓	✓	✓	R	R	✓	∞	∞	R	R	R
r_fctl-dims-mismatchpng IHDRacTLfcTLIDATIEND fcTL for the IDAT frame declares 2x2 for a 13x15 image. §11.3.6.2 says the default image's fcTL has offset 0 and the IHDR's size; §13.1 says a decoder should fall back to the static image. expected: recover, does not conform expected30 match 191 of 195 pixels differ2: wuffs, wuffs-head 193 of 195 pixels differ1: upng-head	✓	✓	R	R	✓	✓	R	R	✓	✓	✓	✓	✓	R	✓	✓	✓	✓	✓	✓	✓	R	R	✓	✓	✓	✓	✓	✓	R	R	✓	!	≠	≠	R	R
r_fctl-dispose-3png IHDRacTLfcTLIDATIEND fcTL for the IDAT frame with dispose_op 3, which is undefined. §11.3.6.2 defines dispose_op 0, 1 and 2; §13.1 says a decoder should fall back to the static image. expected: recover, does not conform expected35 match	✓	✓	R	R	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	R	✓	✓	R	R	✓	✓	✓	✓	✓	✓	✓	✓	R	R	✓	✓	✓	R	R	R
r_fdat-without-fctlpng IHDRIDATacTLfdATIEND acTL after IDAT, fdAT with no fcTL. §11.3.6.1 says acTL comes before IDAT; a decoder should ignore a late one and show the static image. expected: recover, does not conform spec: §5.6 expected40 match	✓	✓	R	R	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	R	R	✓	✓	✓	✓	✓	✓	✓	✓	✓	R	R	✓	✓	✓
y_chunk-idotpng IHDRiDOTIDAT ×2IEND iDOT with segments of 8, 7 rows, each in its own IDAT after a full flush. expected: display, conforms; strict: idot#public-name expected44 match	✓	✓	R	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓
y_chunk-idot-1png IHDRiDOTIDATIEND iDOT with segments of 15 rows, each in its own IDAT after a full flush. expected: display, conforms; strict: idot#public-name expected44 match	✓	✓	R	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓
y_chunk-idot-3png IHDRiDOTIDAT ×3IEND iDOT with segments of 5, 5, 5 rows, each in its own IDAT after a full flush. expected: display, conforms; strict: idot#public-name expected44 match	✓	✓	R	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓
y_chunk-idot-after-srgbpng IHDRsRGBiDOTIDAT ×2IEND sRGB, then iDOT: offsets count from iDOT, so they are unchanged. expected: display, conforms; strict: idot#public-name expected44 match	✓	✓	R	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓
y_chunk-idot-before-srgbpng IHDRiDOTsRGBIDAT ×2IEND iDOT, then sRGB: the first offset is 53. expected: display, conforms; strict: idot#public-name expected44 match	✓	✓	R	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓
y_chunk-idot-stalepng IHDRiDOTIDATIEND an optimizer merged the IDAT chunks and passed iDOT through unchanged: the second offset lands inside the merged IDAT's data. iDOT is only a decoding hint, so a decoder shows the same image as without it. expected: display, does not conform; strict: idot#public-name spec: DECISIONS.md, Apple iDOT expected44 match	✓	✓	R	A	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓
y_chunk-idot-shortpng IHDRiDOTIDAT ×2IEND iDOT of six of its seven words: no second segment offset. iDOT is only a decoding hint, so a decoder shows the same image as without it. expected: display, does not conform; strict: idot#public-name spec: DECISIONS.md, Apple iDOT expected44 match	✓	✓	R	R	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓
y_chunk-idot-emptypng IHDRiDOTIDAT ×2IEND zero-length iDOT. iDOT is only a decoding hint, so a decoder shows the same image as without it. expected: display, does not conform; strict: idot#public-name spec: DECISIONS.md, Apple iDOT expected44 match	✓	✓	R	R	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓
y_apng-idat-is-framepng IHDRacTLfcTLIDATfcTLfdATIEND acTL(2, 0); fcTL 13x15 before IDAT, so the IDAT image is frame 1; frame 2 is the picture's top-left 6x7 at (3, 4). §4.9.1 says an fcTL before IDAT makes the static image the first frame. expected: display, conforms spec: §11.3.6.3, §4.9.2 expected44 match	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓
y_apng-idat-not-framepng IHDRacTLIDATfcTLfdATIEND acTL(1, 0); no fcTL before IDAT, so the IDAT image is not part of the animation, whose one frame is the picture's top-left 6x7 at (3, 4); the expected pixels are the static image. §4.9.1 says without an fcTL before IDAT, the static image is not part of the animation. expected: display, conforms spec: §4.9.2 expected38 match 195 of 195 pixels differ3: wuffs, wuffs-head, upng-head	✓	✓	✓	✓	✓	✓	R	R	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	!	≠	≠	✓	✓
y_apng-frames-8png IHDRacTLfcTLIDATfcTLfdATfcTLfdATfcTLfdATfcTLfdATfcTLfdATfcTLfdATfcTLfdATIEND acTL(8, 0): the IDAT image, then 7 frames each showing the picture's top-left 4x4, at (9, 0), (0, 11), (9, 11), (4, 5), (2, 2), (7, 8), (5, 11); sequence numbers 0..14. §4.9.1 says an fcTL before IDAT makes the static image the first frame. expected: display, conforms spec: §4.9.2 expected44 match	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓
y_apng-frame-bottom-rightpng IHDRacTLfcTLIDATfcTLfdATIEND frame 2 is the picture's top-left 5x5 at (8, 10): its region touches the right and bottom edges. expected: display, conforms spec: §11.3.6.2, §4.9.2 expected44 match	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓
y_apng-dispose-backgroundpng IHDRacTLfcTLIDATfcTLfdATIEND as apng-idat-is-frame, with dispose_op 1 (background) on the IDAT frame. expected: display, conforms spec: §11.3.6.2, §4.9.2 expected44 match	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓
y_apng-dispose-previouspng IHDRacTLfcTLIDATfcTLfdATIEND as apng-idat-is-frame, with dispose_op 2 (previous) on the IDAT frame, the first frame (treated as background). expected: display, conforms spec: §11.3.6.2, §4.9.2 expected43 match	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	R	✓	✓	✓	✓
y_apng-blend-overpng IHDRacTLfcTLIDATfcTLfdATIEND as apng-idat-is-frame, with blend_op 1 (over) on frame 2. expected: display, conforms spec: §11.3.6.2, §4.9.2 expected44 match	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓
y_apng-delay-zeropng IHDRacTLfcTLIDATfcTLfdATIEND as apng-idat-is-frame, with delay_num 0 on both frames. expected: display, conforms spec: §11.3.6.2, §4.9.2 expected44 match	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓
y_apng-delay-den-zeropng IHDRacTLfcTLIDATfcTLfdATIEND as apng-idat-is-frame, with delay_den 0 on both frames (it means 100). expected: display, conforms spec: §11.3.6.2, §4.9.2 expected44 match	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓
y_apng-num-plays-3png IHDRacTLfcTLIDATfcTLfdATIEND as apng-idat-is-frame, with acTL(2, 3): three plays. expected: display, conforms spec: §11.3.6.2, §4.9.2 expected44 match	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓
y_apng-fdat-splitpng IHDRacTLfcTLIDATfcTLfdAT ×3IEND as apng-idat-is-frame, with frame 2's zlib stream in three fdAT chunks, sequence numbers 2, 3, 4. expected: display, conforms spec: §11.3.6.2, §4.9.2 expected44 match	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓
y_apng-p8-trnspng IHDRPLTEacTLtRNSfcTLIDATfcTLfdATIEND as apng-idat-is-frame on p8 with tRNS 00: entry 0 transparent in every frame. expected: display, conforms spec: §11.3.1.1, §11.3.6.3, §4.9.2 expected44 match	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓
y_apng-g1png IHDRacTLfcTLIDATfcTLfdATIEND as apng-idat-is-frame on g1. Table 12 in §11.2.1 lists this combination, and decoders must support every one. expected: display, conforms spec: Table 12, §15.3.3, §11.3.6.3, §4.9.2 expected41 match 94 of 195 pixels differ1: upng	✓	✓	✓	✓	✓	✓	R	R	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	≠	✓	✓	✓	✓
y_apng-rgb8png IHDRacTLfcTLIDATfcTLfdATIEND as apng-idat-is-frame on rgb8. Table 12 in §11.2.1 lists this combination, and decoders must support every one. expected: display, conforms spec: Table 12, §15.3.3, §11.3.6.3, §4.9.2 expected44 match	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓
y_apng-rgba16png IHDRacTLfcTLIDATfcTLfdATIEND as apng-idat-is-frame on rgba16. Table 12 in §11.2.1 lists this combination, and decoders must support every one. expected: display, conforms spec: Table 12, §15.3.3, §11.3.6.3, §4.9.2 expected38 match matches the reference; color under alpha 0 preserved; 16→8 high byte6: upng, pillow, chunky_png, upng-head, pillow-head, chunky_png-head	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓
r_apng-sequence-first-not-zeropng IHDRacTLfcTLIDATfcTLfdATIEND as apng-idat-is-frame; the first fcTL has sequence number 1 (1, 2, 3). §4.9.2 says the sequence numbers run 0, 1, 2, … with no gaps, and a decoder treats anything else as an error; §13.1 says it should fall back to the static image. expected: recover, does not conform expected37 match	✓	✓	R	R	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	R	✓	✓	✓	✓	R	R	✓	✓	✓	✓	✓	✓	R	R	✓	✓	✓	R	✓	✓
r_apng-sequence-gappng IHDRacTLfcTLIDATfcTLfdATIEND as apng-idat-is-frame; the fdAT's sequence number skips 2 (0, 1, 3). §4.9.2 says the sequence numbers run 0, 1, 2, … with no gaps, and a decoder treats anything else as an error; §13.1 says it should fall back to the static image. expected: recover, does not conform expected44 match	✓	✓	R	R	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓
r_apng-sequence-out-of-orderpng IHDRacTLfcTLIDATfcTLfdATIEND as apng-idat-is-frame; the fdAT's sequence number 1 is lower than its fcTL's 2 (0, 2, 1). §4.9.2 says the sequence numbers run 0, 1, 2, … with no gaps, and a decoder treats anything else as an error; §13.1 says it should fall back to the static image. expected: recover, does not conform expected44 match	✓	✓	R	R	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓
r_apng-num-frames-morepng IHDRacTLfcTLIDATfcTLfdATIEND acTL says 3 frames, there are two fcTL. §11.3.6.1 says the frame count matches the fcTL chunks; §13.1 says a decoder should fall back to the static image. expected: recover, does not conform expected44 match	✓	✓	R	R	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓
r_apng-num-frames-fewerpng IHDRacTLfcTLIDATfcTLfdATIEND acTL says 1 frame, there are two fcTL. §11.3.6.1 says the frame count matches the fcTL chunks; §13.1 says a decoder should fall back to the static image. expected: recover, does not conform expected44 match	✓	✓	R	R	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓
r_apng-fctl-without-actlpng IHDRIDATfcTLfdATIEND fcTL and fdAT after IDAT with no acTL: not an APNG, the IDAT image is all there is. §4.9.1 says a file is an APNG only with an acTL before IDAT; without one, a decoder shows the static image. expected: recover, does not conform expected42 match	✓	✓	A	A	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	R	R	✓	✓	✓
r_apng-fctl-without-fdatpng IHDRacTLfcTLIDATfcTLIEND acTL(2, 0) and a second fcTL after IDAT with no fdAT: frame 2 has no data. §11.3.6.3 says every frame after the first has an fdAT; §13.1 says a decoder should fall back to the static image. expected: recover, does not conform expected42 match	✓	✓	R	R	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	R	R	✓	✓	✓
r_apng-actl-duppng IHDRacTL ×2fcTLIDATfcTLfdATIEND as apng-idat-is-frame with its acTL twice. Table 7 in §5.6 allows this chunk once; a decoder should ignore the second. expected: recover, does not conform spec: Table 7, §13.1 expected42 match	✓	✓	R	R	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	R	✓	✓
r_apng-fctl-uint31png IHDRacTLfcTLIDATfcTLIEND acTL(1, 0) and the IDAT frame's fcTL, then a further fcTL after IDAT whose x_offset is 2^31, past the PNG integer range (the delay fields are two bytes and cannot hold it): that fcTL is ignored, which leaves a valid one-frame animation. §7.1 limits four-byte integers to 2^31−1; a decoder should ignore an ancillary chunk that breaks that. expected: recover, does not conform expected38 match	✓	✓	R	R	✓	✓	✓	✓	✓	✓	✓	✓	✓	R	✓	✓	✓	✓	✓	✓	✓	R	R	✓	✓	✓	✓	✓	✓	✓	✓	✓	R	R	✓	✓	✓
r_apng-two-fctl-before-idatpng IHDRacTLfcTL ×2IDATIEND acTL(2, 0) and two fcTL for the full image before IDAT: only one may precede IDAT. Table 7 in §5.6 allows one fcTL before IDAT; §13.1 says a decoder should fall back to the static image. expected: recover, does not conform spec: Table 7 expected38 match	✓	✓	R	R	✓	✓	R	R	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	R	R	R	✓	✓
r_apng-frame-outsidepng IHDRacTLfcTLIDATfcTLfdATIEND frame 2 is 6x7 at (9, 10): past the right and bottom edges. §11.3.6.2 says a frame fits inside the image; §13.1 says a decoder should fall back to the static image. expected: recover, does not conform expected42 match	✓	✓	R	R	✓	✓	✓	✓	✓	✓	✓	✓	✓	R	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓
r_apng-frame-zero-sizepng IHDRacTLfcTLIDATfcTLfdATIEND frame 2's fcTL has width 0, its fdAT an empty zlib stream. §11.3.6.2 says a frame's width and height are nonzero; §13.1 says a decoder should fall back to the static image. expected: recover, does not conform expected42 match	✓	✓	R	R	✓	✓	✓	✓	✓	✓	✓	✓	✓	R	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓
r_apng-fdat-bad-adlerpng IHDRacTLfcTLIDATfcTLfdATIEND as apng-idat-is-frame, with frame 2's Adler-32 wrong: a decoder that inflates frames it never shows reaches it. §11.3.6.3 makes a frame's data a zlib stream like IDAT's; a decoder should show the static image when a frame's stream is invalid. expected: recover, does not conform spec: §10.1 expected43 match	✓	✓	A	A	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	R	✓	✓	✓	✓
r_apng-fdat-emptypng IHDRacTLfcTLIDATfcTLfdAT ×2IEND as apng-idat-is-frame with a 3-byte fdAT before frame 2's fdAT: too short even for a sequence number. §11.3.6.3 says fdAT holds at least its 4-byte sequence number; §13.1 says a decoder should fall back to the static image. expected: recover, does not conform expected41 match	✓	✓	R	R	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	R	R	✓	R	✓
i_apng-truncated-fdatpng IHDRacTLfcTLIDATfcTLfdAT as apng-idat-is-frame, cut off in the middle of frame 2's fdAT: no IEND. §13.1 says a datastream that ends mid-chunk is corrupt, and a decoder may treat that as fatal. expected: may-reject, does not conform expected15 match	✓	✓	R	R	R	R	✓	✓	R	R	R	R	R	R	✓	R	R	✓	R	R	R	✓	✓	R	R	R	R	R	R	✓	✓	R	R	✓	✓	R	✓
y_apng-idat-not-frame-3png IHDRacTLIDATfcTLfdATfcTLfdATfcTLfdATIEND acTL(3, 0); no fcTL before IDAT; three frames after it, none at the origin. §4.9.1 says without an fcTL before IDAT, the static image is not part of the animation. expected: display, conforms spec: §4.9.2 expected38 match 195 of 195 pixels differ3: wuffs, wuffs-head, upng-head	✓	✓	✓	✓	✓	✓	R	R	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	!	≠	≠	✓	✓
r_apng-fdat-no-fctlpng IHDRacTLIDATfdATIEND acTL(1, 0), IDAT, then an fdAT with no fcTL anywhere: the frame count is off too. §11.3.6.3 says every frame has exactly one fcTL; §13.1 says a decoder should fall back to the static image. expected: recover, does not conform spec: §11.3.6.2 expected36 match	✓	✓	R	R	✓	✓	R	R	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	R	R	✓	✓	✓	✓	✓	✓	✓	✓	✓	R	R	R	✓	✓
r_apng-fctl-fctl-fdatpng IHDRacTLIDATfcTL ×2fdATIEND acTL(2, 0); after IDAT two fcTL in a row, then one fdAT: the first frame after IDAT has no data. §11.3.6.3 says every frame after the first has an fdAT; §13.1 says a decoder should fall back to the static image. expected: recover, does not conform expected38 match 195 of 195 pixels differ2: ffmpeg, ffmpeg-head 195 of 195 pixels differ1: upng-head	✓	✓	R	R	✓	✓	≠	≠	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	!	≠	R	✓	✓
r_apng-actl-uint31png IHDRacTLfcTLIDATfcTLfdATIEND acTL num_frames 2^31 + 1: out of range, so the acTL is ignored and the fcTL chunks have none. §7.1 limits four-byte integers to 2^31−1; a decoder should ignore an ancillary chunk that breaks that. expected: recover, does not conform expected43 match	✓	✓	R	R	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	R	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓
r_apng-fctl-before-idat-no-actlpng IHDRfcTLIDATIEND an fcTL for the IDAT image, before IDAT, with no acTL. §4.9.1 says a file is an APNG only with an acTL before IDAT; without one, a decoder shows the static image. expected: recover, does not conform expected44 match	✓	✓	A	A	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓
r_apng-fctl-region-before-idat-no-actlpng IHDRfcTLIDATIEND an fcTL before IDAT naming a 6x7 region at (3, 4), with no acTL: not an APNG, and not the default image's shape either. §4.9.1 says a file is an APNG only with an acTL before IDAT; without one, a decoder shows the static image. expected: recover, does not conform expected36 match	✓	✓	R	R	✓	✓	✓	✓	✓	✓	✓	✓	✓	R	✓	✓	✓	✓	✓	✓	✓	R	R	✓	✓	✓	✓	✓	✓	R	R	✓	✓	✓	✓	R	R
y_sbit-g8-4png IHDRsBITIDATIEND g8 with sBIT 4: informational, the samples decode as stored. expected: display, conforms spec: §11.3.2.4 expected43 match 157 of 195 pixels differ1: pypng	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	≠	✓	✓	✓	✓	✓	✓	✓	✓	✓
y_sbit-rgb16-565png IHDRsBITIDATIEND rgb16 with sBIT 5 6 5: informational, the samples decode as stored. expected: display, conforms spec: §11.3.2.4 expected37 match matches the reference; 16→8 high byte6: upng, pillow, chunky_png, upng-head, pillow-head, chunky_png-head 192 of 195 pixels differ1: pypng	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	≠	✓	✓	✓	✓	✓	✓	✓	✓	✓
y_sbit-rgb8-555png IHDRsBITIDATIEND rgb8 with sBIT 5 5 5: informational, the samples decode as stored. expected: display, conforms spec: §11.3.2.4 expected43 match 192 of 195 pixels differ1: pypng	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	≠	✓	✓	✓	✓	✓	✓	✓	✓	✓
y_sbit-p8-444png IHDRsBITPLTEIDATIEND p8 with sBIT 4 4 4: informational, the samples decode as stored. expected: display, conforms spec: §11.3.2.4 expected43 match 192 of 195 pixels differ1: pypng	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	≠	✓	✓	✓	✓	✓	✓	✓	✓	✓
y_sbit-ga8-4-4png IHDRsBITIDATIEND ga8 with sBIT 4 4: informational, the samples decode as stored. expected: display, conforms spec: §11.3.2.4 expected41 match 166 of 195 pixels differ3: pypng, pngtopam, pngtopam-head	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	≠	≠	≠	✓	✓	✓	✓	✓	✓	✓	✓	✓
y_sbit-rgba16-888-8png IHDRsBITIDATIEND rgba16 with sBIT 8 8 8 8: informational, the samples decode as stored. expected: display, conforms spec: §11.3.2.4 expected35 match matches the reference; color under alpha 0 preserved; 16→8 high byte6: upng, pillow, chunky_png, upng-head, pillow-head, chunky_png-head 192 of 195 pixels differ3: pypng, pngtopam, pngtopam-head	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	≠	≠	≠	✓	✓	✓	✓	✓	✓	✓	✓	✓
y_bkgd-g8png IHDRbKGDIDATIEND g8 with bKGD the picture's commonest gray, 149: a decoder must not composite onto it. expected: display, conforms spec: §11.3.4.1 expected44 match	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓
y_bkgd-g16png IHDRbKGDIDATIEND g16 with bKGD the picture's commonest gray, 8687: a decoder must not composite onto it. expected: display, conforms spec: §11.3.4.1 expected40 match matches the reference; 16→8 high byte4: upng, chunky_png, upng-head, chunky_png-head	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓
y_bkgd-rgb8png IHDRbKGDIDATIEND rgb8 with bKGD the top-left pixel's color (13, 31, 128): a decoder must not composite onto it. expected: display, conforms spec: §11.3.4.1 expected44 match	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓
y_bkgd-rgb16png IHDRbKGDIDATIEND rgb16 with bKGD the top-left pixel's color (3277, 7864, 32768): a decoder must not composite onto it. expected: display, conforms spec: §11.3.4.1 expected38 match matches the reference; 16→8 high byte6: upng, pillow, chunky_png, upng-head, pillow-head, chunky_png-head	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓
y_bkgd-p8png IHDRPLTEbKGDIDATIEND p8 with bKGD palette index 0: a decoder must not composite onto it. expected: display, conforms spec: §11.3.4.1 expected44 match	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓
y_bkgd-ga8png IHDRbKGDIDATIEND ga8 with bKGD gray 34, the commonest gray: a decoder must not composite onto it. expected: display, conforms spec: §11.3.4.1 expected44 match	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓
y_bkgd-rgba8png IHDRbKGDIDATIEND rgba8 with bKGD the top-left pixel's color (13, 31, 128): a decoder must not composite onto it. expected: display, conforms spec: §11.3.4.1 expected44 match	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓
y_bkgd-trns-g8png IHDRtRNSbKGDIDATIEND g8 with bKGD 149, tRNS gray 149: the tRNS pixels have alpha 0, and a decoder that composites onto the background shows them opaque. expected: display, conforms spec: §11.3.4.1, §11.3.1.1 expected34 match matches the reference; color under alpha 0 zeroed6: wuffs, pngjs, chunky_png, wuffs-head, pngjs-head, chunky_png-head 18 of 195 pixels differ4: fast-png, opencv, fast-png-head, opencv-head	✓	✓	✓	✓	✓	≠	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	≠	≠	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓
y_bkgd-trns-rgb8png IHDRtRNSbKGDIDATIEND rgb8 with bKGD (13, 31, 128), tRNS (13, 31, 128): the tRNS pixels have alpha 0, and a decoder that composites onto the background shows them opaque. expected: display, conforms spec: §11.3.4.1, §11.3.1.1 expected32 match matches the reference; color under alpha 0 zeroed6: wuffs, pngjs, chunky_png, wuffs-head, pngjs-head, chunky_png-head 13 of 195 pixels differ6: fast-png, pngtopam, graphicsmagick, graphicsmagick-head, fast-png-head, pngtopam-head	✓	✓	✓	✓	✓	≠	✓	✓	✓	≠	≠	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	≠	M	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓
y_bkgd-trns-p8png IHDRPLTEtRNSbKGDIDATIEND p8 with bKGD index 0, tRNS 00: the tRNS pixels have alpha 0, and a decoder that composites onto the background shows them opaque. expected: display, conforms spec: §11.3.4.1, §11.3.1.1 expected44 match	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓
y_iccp-rgbpng IHDRiCCPIDATIEND iCCP holding an RGB profile on rgb8; the profile is a 132-byte header with an empty tag table, so it maps nothing. expected: display, conforms spec: §11.3.2.3 expected44 match	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓
y_iccp-gray-on-graypng IHDRiCCPIDATIEND iCCP holding a GRAY profile on g8; the profile is a 132-byte header with an empty tag table, so it maps nothing. expected: display, conforms spec: §11.3.2.3 expected44 match	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓
r_iccp-gray-on-rgbpng IHDRiCCPIDATIEND iCCP holding a GRAY profile on rgb8; the profile is a 132-byte header with an empty tag table, so it maps nothing. §11.3.2.3 says the profile's color space matches the image, RGB for color and gray for grayscale; a decoder should ignore a mismatched one. expected: recover, does not conform expected44 match	✓	✓	A	A	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓
r_iccp-cmyk-on-rgbpng IHDRiCCPIDATIEND iCCP holding a CMYK profile on rgb8; the profile is a 132-byte header with an empty tag table, so it maps nothing. §11.3.2.3 says the profile's color space matches the image, RGB for color and gray for grayscale; a decoder should ignore a mismatched one. expected: recover, does not conform expected44 match	✓	✓	A	A	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓
r_iccp-rgb-on-graypng IHDRiCCPIDATIEND iCCP holding an RGB profile on g8; the profile is a 132-byte header with an empty tag table, so it maps nothing. §11.3.2.3 says the profile's color space matches the image, RGB for color and gray for grayscale; a decoder should ignore a mismatched one. expected: recover, does not conform expected44 match	✓	✓	A	A	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓
y_text-largepng IHDRtEXtIDATIEND one tEXt holding 1 MiB of 'a'. expected: display, conforms spec: §11.3.3.2 expected44 match	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓
y_itxt-largepng IHDRiTXtIDATIEND one uncompressed iTXt holding 1 MiB of 'a'. expected: display, conforms spec: §11.3.3.4 expected44 match	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓
r_itxt-null-in-textpng IHDRiTXtIDATIEND iTXt whose text holds a NUL. §11.3.3.4 says neither the translated keyword nor the text may contain a null; a decoder should ignore the chunk otherwise. expected: recover, does not conform expected44 match	✓	✓	A	A	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓
y_exif-validpng IHDReXIfIDATIEND eXIf: little-endian TIFF header and one IFD with Orientation 1. expected: display, conforms spec: §11.3.4.5, Extensions 1.5.0 §3.7 expected44 match	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓
y_exif-orientation-6png IHDReXIfIDATIEND eXIf with Orientation 6, rotate 90° clockwise to display; nothing in PNG says to apply it, so the expected pixels are unrotated, and a decoder that rotates counts as wrong. expected: display, conforms spec: §11.3.4.5, Extensions 1.5.0 §3.7 expected42 match 15x13 instead of 13x152: ffmpeg, ffmpeg-head	✓	✓	✓	✓	✓	✓	≠	≠	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓
y_hist-validpng IHDRPLTEhISTIDATIEND p8 with a hIST giving each palette entry its pixel count (all nonzero). expected: display, conforms spec: §11.3.4.2 expected44 match	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓
y_mdcv-clli-validpng IHDRcICPmDCVcLLIIDATIEND cICP 9 16 0 1 (BT.2020, PQ, full range), mDCV with BT.2020 primaries, D65, 1000 and 0.0001 cd/m2, and cLLI 1000 and 400 cd/m2; the samples decode as stored. expected: display, conforms spec: §11.3.2.7, §11.3.2.8 expected44 match	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓
y_trns-adam7-g1-whitepng IHDRtRNSIDATIEND interlaced, random filter per scanline, tRNS names white (1): those pixels have alpha 0. §8.1 says decoders are required to read interlaced images. expected: display, conforms spec: §11.3.1.1, §13.10 expected29 match matches the reference; color under alpha 0 zeroed6: wuffs, pngjs, chunky_png, wuffs-head, pngjs-head, chunky_png-head 77 of 195 pixels differ5: ffmpeg, java-imageio, opencv, ffmpeg-head, opencv-head 12 of 195 pixels differ1: upng-head 89 of 195 pixels differ1: upng	✓	✓	✓	✓	✓	R	≠	≠	✓	✓	✓	✓	✓	✓	≠	✓	✓	✓	✓	≠	≠	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	≠	≠	✓	✓	✓
y_trns-adam7-g2-midpng IHDRtRNSIDATIEND interlaced, random filter per scanline, tRNS names mid (1): those pixels have alpha 0. §8.1 says decoders are required to read interlaced images. expected: display, conforms spec: §11.3.1.1, §13.10 expected27 match 103 of 195 pixels differ7: ffmpeg, java-imageio, pillow, opencv, ffmpeg-head, pillow-head, opencv-head matches the reference; color under alpha 0 zeroed6: wuffs, pngjs, chunky_png, wuffs-head, pngjs-head, chunky_png-head 118 of 195 pixels differ1: upng 1 of 195 pixels differ1: upng-head	✓	✓	✓	✓	✓	R	≠	≠	✓	✓	✓	✓	✓	✓	≠	✓	✓	✓	✓	≠	≠	≠	≠	✓	✓	✓	✓	✓	✓	✓	✓	✓	≠	≠	✓	✓	✓
y_trns-adam7-g4-midpng IHDRtRNSIDATIEND interlaced, random filter per scanline, tRNS names mid (6): those pixels have alpha 0. §8.1 says decoders are required to read interlaced images. expected: display, conforms spec: §11.3.1.1, §13.10 expected28 match 26 of 195 pixels differ7: ffmpeg, java-imageio, pillow, opencv, ffmpeg-head, pillow-head, opencv-head matches the reference; color under alpha 0 zeroed6: wuffs, pngjs, chunky_png, wuffs-head, pngjs-head, chunky_png-head 122 of 195 pixels differ1: upng	✓	✓	✓	✓	✓	R	≠	≠	✓	✓	✓	✓	✓	✓	≠	✓	✓	✓	✓	≠	≠	≠	≠	✓	✓	✓	✓	✓	✓	✓	✓	✓	≠	✓	✓	✓	✓
y_trns-adam7-g8-midpng IHDRtRNSIDATIEND interlaced, random filter per scanline, tRNS names mid (149): those pixels have alpha 0. §8.1 says decoders are required to read interlaced images. expected: display, conforms spec: §11.3.1.1, §13.10 expected33 match matches the reference; color under alpha 0 zeroed6: wuffs, pngjs, chunky_png, wuffs-head, pngjs-head, chunky_png-head 18 of 195 pixels differ4: fast-png, opencv, fast-png-head, opencv-head 4 of 195 pixels differ1: upng-head	✓	✓	✓	✓	✓	≠	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	≠	≠	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	≠	✓	✓	✓
y_trns-adam7-g16-midpng IHDRtRNSIDATIEND interlaced, random filter per scanline, tRNS names mid (8687): those pixels have alpha 0. §8.1 says decoders are required to read interlaced images. expected: display, conforms spec: §11.3.1.1, §13.10 expected27 match 13 of 195 pixels differ9: zune-png, imagesharp, fast-png, pillow, opencv, imagesharp-head, fast-png-head, pillow-head, opencv-head matches the reference; color under alpha 0 zeroed4: wuffs, pngjs, wuffs-head, pngjs-head matches the reference; color under alpha 0 zeroed; 16→8 high byte2: chunky_png, chunky_png-head matches the reference; color under alpha 0 preserved; 16→8 high byte1: upng 193 of 195 pixels differ1: upng-head	✓	✓	✓	✓	✓	≠	✓	✓	✓	✓	✓	✓	✓	≠	✓	✓	✓	✓	✓	≠	≠	≠	≠	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	≠	✓	≠	✓
y_trns-adam7-rgb8-midpng IHDRtRNSIDATIEND interlaced, random filter per scanline, tRNS names mid (13, 31, 128): those pixels have alpha 0. §8.1 says decoders are required to read interlaced images. expected: display, conforms spec: §11.3.1.1, §13.10 expected32 match matches the reference; color under alpha 0 zeroed6: wuffs, pngjs, chunky_png, wuffs-head, pngjs-head, chunky_png-head 13 of 195 pixels differ6: fast-png, pngtopam, graphicsmagick, graphicsmagick-head, fast-png-head, pngtopam-head	✓	✓	✓	✓	✓	≠	✓	✓	✓	≠	≠	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	≠	M	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓
y_trns-adam7-rgb16-midpng IHDRtRNSIDATIEND interlaced, random filter per scanline, tRNS names mid (3277, 7864, 32768): those pixels have alpha 0. §8.1 says decoders are required to read interlaced images. expected: display, conforms spec: §11.3.1.1, §13.10 expected27 match 13 of 195 pixels differ7: zune-png, imagesharp, fast-png, pngtopam, imagesharp-head, fast-png-head, pngtopam-head matches the reference; color under alpha 0 zeroed4: wuffs, pngjs, wuffs-head, pngjs-head matches the reference; color under alpha 0 zeroed; 16→8 high byte2: chunky_png, chunky_png-head 192 of 195 pixels differ2: pillow, pillow-head matches the reference; color under alpha 0 preserved; 16→8 high byte1: upng 192 of 195 pixels differ1: upng-head	✓	✓	✓	✓	✓	≠	✓	✓	✓	✓	✓	✓	✓	≠	✓	✓	✓	✓	✓	✓	✓	≠	≠	✓	✓	≠	M	✓	✓	✓	✓	✓	✓	≠	✓	≠	✓
y_trns-adam7-p8-entry0png IHDRPLTEtRNSIDATIEND interlaced p8, random filter per scanline, tRNS of one byte 0: entry 0 transparent. §8.1 says decoders are required to read interlaced images. expected: display, conforms spec: §11.3.1.1, §13.10 expected44 match	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓
i_dims-huge-short-datapng IHDRPLTEIDATIEND IHDR 32769x65580 p8 (over 2 GiB of pixels), image data for the first two rows only (the picture's rows, then index 0). §13.1 says a decoder may treat an early end of the image data as fatal. The image is incomplete, so what a decoder shows for it isn't judged. expected: may-reject, does not conform	R	R	A	A	R	∞	R	R	∞	R	R	R	R	R	R	R	R	R	∞	R	R	R	R	R	R	R	R	!	!	R	R	R	∞	∞	∞	R	R
i_dims-huge-short-data-adam7png IHDRPLTEIDATIEND IHDR 1x2147483647 p8 interlaced, image data for one row of reduced image 1. §13.1 says a decoder may treat an early end of the image data as fatal. The image is incomplete, so what a decoder shows for it isn't judged. expected: may-reject, does not conform	R	R	A	A	∞	∞	R	R	∞	R	R	R	R	R	R	R	R	R	∞	R	R	R	R	R	R	R	R	∞	∞	R	R	R	∞	∞	R	R	R
i_dims-tall-short-datapng IHDRIDATIEND IHDR 32x1000001 rgba8, not interlaced, image data for the first two rows only (the picture's, then transparent black): a decoder that walks every declared row takes a million steps for nothing. §13.1 says a decoder may treat an early end of the image data as fatal. The image is incomplete, so what a decoder shows for it isn't judged. expected: may-reject, does not conform 32×1000001no reference pixels8: imagesharp, pngjs, upng, pillow, imagesharp-head, pngjs-head, upng-head, pillow-head	R	R	A	A	R	R	R	R	R	R	R	R	⧗	A	R	R	R	R	R	R	R	A	A	A	A	R	R	!	!	R	R	R	A	A	R	R	R
y_dims-wide-32768png IHDRIDATIEND 32768x1 rgba8: the picture's top row (sky, the fade at its right) repeated across; one zlib stream. Table 12 in §11.2.1 lists this combination, and decoders must support every one. expected: display, conforms spec: Table 12, §15.3.3 32768×1expected42 match	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	R	R
y_dims-tall-32768png IHDRIDATIEND 1x32768 rgba8: the picture's left column repeated down; one zlib stream. Table 12 in §11.2.1 lists this combination, and decoders must support every one. expected: display, conforms spec: Table 12, §15.3.3 1×32768expected42 match	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	✓	R	R
n_chunk-cgbipng CgBIIHDRIDATIEND Apple CgBI as Xcode writes it: a CgBI chunk before IHDR, raw DEFLATE image data without zlib framing, samples in BGRA order, color premultiplied by alpha. §11.2.1 says IHDR comes first, so that's a fatal error. expected: must-reject, does not conform spec: §5.6 no reference pixels3: stb_image, stb_image-head, upng-head	R	R	R	R	R	R	R	R	R	R	R	R	R	R	R	R	R	R	R	R	R	R	R	R	R	R	R	R	R	R	R	A	R	A	R	R	R
n_signature-wrongpng signatureIHDRIDATIEND first signature byte 0x88 instead of 0x89. §5.2 says a decoder should check all eight signature bytes, so that's a fatal error. expected: must-reject, does not conform spec: §13.1	R	R	R	R	R	R	R	R	R	R	R	R	R	R	R	R	R	R	R	R	R	R	R	R	R	R	R	R	R	R	R	R	R	R	R	R	R
n_signature-shortpng signature the first 4 signature bytes and nothing else. §5.2 says a decoder should check all eight signature bytes, so that's a fatal error. expected: must-reject, does not conform spec: §13.1	R	R	R	R	R	R	R	R	R	R	R	R	R	R	R	R	R	R	R	R	R	R	R	R	R	R	R	R	R	R	R	R	R	R	R	R	R
i_iend-truncatedpng IHDRIDATIEND the datastream ends after IEND's type, before its CRC. §13.1 says a datastream that ends mid-chunk is corrupt, and a decoder may treat that as fatal. expected: may-reject, does not conform expected20 match	✓	✓	R	R	R	✓	R	R	R	R	R	R	R	✓	✓	R	R	✓	R	R	R	✓	✓	R	R	R	R	R	R	✓	✓	✓	✓	✓	✓	R	✓
n_plte-missing-palpng IHDRIDATIEND p8 with no PLTE anywhere. §11.2.2 says an indexed image has a PLTE before IDAT, so that's a fatal error. expected: must-reject, does not conform spec: §11.2.1, §5.6 no reference pixels2: fast-png, fast-png-head no reference pixels2: ffmpeg, ffmpeg-head no reference pixels2: pillow, pillow-head no reference pixels1: zune-png	R	R	R	R	R	A	A	A	R	R	R	R	R	R	R	R	R	R	R	R	R	A	A	R	R	R	R	R	R	R	R	R	R	R	R	A	R