APNG Tests

There is a test suite for APNG , from 2007, which relies on visual 
appraisal of the results.

I have been converting it to Web Platform Tests reftests, which can be 
scored automatically; each test just needs a delay (animation duration 
plus another second to be sure) before the final result is compared to a 
static reference representing the final appearance.

A few have to be manual tests, which are not run automatically and need 
a human to judge correctness.

Mostly done, I have 25 reftests so far plus 8 manual ones; then I need 
to lint it (WPT is very strict) and get it reviewed. I have been adding 
"rel=help" lines to each test, pointing to the actual spec section being 
tested plus test assertions.

These should all pass (the existing version passes) in all modern browsers.

On 2023-10-27 14:00, Chris Blume (ProgramMax) wrote:
> In a previous email, Chris Lilley said "We need 2 independent 
> implementations of each new feature." He also mentioned our Third 
> Edition test coverage is small.
>
> Any help in those areas would be greatly appreciated.
>
>
> On Fri, Oct 27, 2023 at 1:26 PM Seeger, Chris (NBCUniversal) 
> <Chris.Seeger@nbcuni.com> wrote:
>
>     Yes, I would really like to get the 3^rd edition out the door! 
>     Please let me know if there is anything I can help with.
>
>     Best,
>     Chris Seeger
>
>     *From: *Chris Blume (ProgramMax) <programmax@gmail.com>
>     *Date: *Friday, October 27, 2023 at 1:14 PM
>     *To: *public-png@w3.org <public-png@w3.org>
>     *Subject: *[EXTERNAL] [PNG] Meeting topics - Oct 30th, 2023
>
>     Hello everyone,
>
>     Our next meeting is this coming Monday at 11am Eastern.
>
>     Richard Geldreich and Stephanie Hurlburt from Binomial are joining
>     us. You might know them from their previous work on Basis, the GPU
>     texture format & codec which bridged the gap between block
>     compression (found in GPU texture compression) and stream
>     compression (like deflate).
>
>     I am elated to have them on board. I think having GPU-minded
>     people will help PNG push the future. But GPU-minded AND
>     world-leading compression experts?! We couldn't have been more lucky.
>
>     In our meeting, I'll let them introduce themselves and briefly
>     discuss what they would like to see in the Fourth Edition of the
>     PNG spec.
>
>     Speaking of, the new PNG WG charter has gone through
>     <https://urldefense.com/v3/__https:/www.w3.org/Graphics/PNG/png-2023.html__;!!PIZeeW5wscynRQ!oM86-sOba6Frk5YjQ1iacLQxQr0sdOngOzlF4_12kPkeGR7B13n_OUPE37Sa3_oxAFYbvs1lM74VRHsUKaRM$>.
>     A Fourth Edition is officially on the roadmap!
>
>     But phew, we're not there yet. I would love for Chris Lilley to
>     discuss what we need to wrap up Third Edition and then for us to
>     plan how we're going to do that.
>
>     See you all Monday!
>
-- 
Chris Lilley
@svgeesus
Technical Director @ W3C
W3C Strategy Team, Core Web Design
W3C Architecture & Technology Team, Core Web & Media