Re: [EXTERNAL] Conformance files in PQ, HLG, SDR-BT.709?

Thanks Leo!

It seems like Preview in MacOS is not reading the cicp chunk.  Can you help us fix it?

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________________________________
From: Leo Barnes <lbarnes@apple.com>
Sent: Saturday, December 9, 2023 1:55:15 PM
To: Chris Blume (ProgramMax) <programmax@gmail.com>
Cc: Seeger, Chris (NBCUniversal) <Chris.Seeger@nbcuni.com>; public-png@w3.org <public-png@w3.org>
Subject: Re: [EXTERNAL] Conformance files in PQ, HLG, SDR-BT.709?



On Dec 9, 2023, at 04:13, Chris Blume (ProgramMax) <programmax@gmail.com> wrote:

My understanding (could be wrong) is that a lot of image handling (only PNG?) on Apple platforms happens via OS-provided APIs.

Yes, this is correct. Unless apps have very specific needs they tend to use ImageIO<https://urldefense.com/v3/__https://developer.apple.com/documentation/imageio?language=objc__;!!PIZeeW5wscynRQ!vur_aJ2XTckLKYECOxw6G7JKAv3gyncliPaPK9vGMFJ-PAi3RpaWBa_gHDzyNeSTBGF1z95EWs1Ek7d6$> to parse, decode and encode images. It supports a bunch of image formats (including PNG, JPEG and HEIF) in a format agnostic API.
If ImageIO adds support for a new format or a new feature of an existing format, that tends to then come for free for all apps on all Apple platforms.

For example, if we're concerned about Safari's support of PNG, we actually care about MacOS's / iOS's support.

Yes and no. Safari also tends to backport some things for new versions of Safari on older OS releases.

Cheers,
//Leo


On Fri, Dec 8, 2023 at 6:59 PM Seeger, Chris (NBCUniversal) <Chris.Seeger@nbcuni.com<mailto:Chris.Seeger@nbcuni.com>> wrote:

It appears to be MacOS system wide.  The Photo’s app also reads the CICP chunk.



From: Chris Lilley <chris@w3.org<mailto:chris@w3.org>>
Date: Friday, December 8, 2023 at 4:55 PM
To: Seeger, Chris (NBCUniversal) <Chris.Seeger@nbcuni.com<mailto:Chris.Seeger@nbcuni.com>>, public-png@w3.org<mailto:public-png@w3.org> <public-png@w3.org<mailto:public-png@w3.org>>
Subject: Re: [EXTERNAL] Re: Conformance files in PQ, HLG, SDR-BT.709?

Great, so we can make a reftest which fails if the narrow/full flag is
ignored, put that in web platform tests and file bugs on those
implementations to fix the bug.

On 2023-12-08 16:46, Seeger, Chris (NBCUniversal) wrote:
> You’re not going to believe this, but Apple Compressor and FinalCut
> already recognizing the CICP Chunk correctly (with the exception of
> full-range flag).

--
Chris Lilley
@svgeesus
Technical Director @ W3C
W3C Strategy Team, Core Web Design
W3C Architecture & Technology Team, Core Web & Media