Re: [EXTERNAL] Re: PNG overview slides

Yes, JPEG 1 is definitely focused on photos and so it messes up anything with “hard lines” (e.g., logos, icons, etc.).  both JXL and AVIF address this concern in their lossy versions.

But definitely worth doing some comparisons of our own.  Taking files from places like the Noun Project, FlatIcon and Font Awesome running them through the various options and comparing would be a worthwhile way to determine if that requirement has already been met.

Leonard

From: Chris Blume (ProgramMax) <programmax@gmail.com>
Date: Thursday, November 13, 2025 at 8:35 AM
To: Leonard Rosenthol <lrosenth@adobe.com>
Cc: Seeger, Chris (NBCUniversal) <Chris.Seeger@nbcuni.com>, Chris Lilley <chris@w3.org>, Portable Network Graphics (PNG) Working Group <public-png@w3.org>
Subject: Re: [EXTERNAL] Re: PNG overview slides


EXTERNAL: Use caution when clicking on links or opening attachments.


Good points, Leonard. Agreed.
(And agreed that if 1 format is the goal, JpegXL for example perhaps already solves it.)

Thinking of a W3C-centric, lossy use case off the cuff:
I think people typically associate PNG with logos and icons.
I don't think logos and icons need to be 100% lossless.
I think Jpeg 1 does a bad job with (some) logos and icons, so PNG fills that gap.

But there are surely better lossy options that are well suited for logos and icons (rather than photos).
I feel like many lossy compression formats target photos.
And I feel like W3C would care about logos and icons.
I could see a lossy format that falls under W3C's umbrella and addresses an underserved use case.


On Thu, Nov 13, 2025 at 10:30 PM Leonard Rosenthol <lrosenth@adobe.com<mailto:lrosenth@adobe.com>> wrote:
>1 still image format that developers can use for almost everything
>
Which was the intent for JPEG XL.

Which brings us back to determining whether it (or some other format, such as AVIF or WebP) meets those goals/requirements.

Leonard

From: Seeger, Chris (NBCUniversal) <Chris.Seeger@nbcuni.com<mailto:Chris.Seeger@nbcuni.com>>
Date: Thursday, November 13, 2025 at 8:24 AM
To: Leonard Rosenthol <lrosenth@adobe.com<mailto:lrosenth@adobe.com>>, Chris Blume (ProgramMax) <programmax@gmail.com<mailto:programmax@gmail.com>>, Chris Lilley <chris@w3.org<mailto:chris@w3.org>>
Cc: Portable Network Graphics (PNG) Working Group <public-png@w3.org<mailto:public-png@w3.org>>
Subject: Re: [EXTERNAL] Re: PNG overview slides


EXTERNAL: Use caution when clicking on links or opening attachments.


Hi,

I’m thinking in a similar but slightly different way. Why have different image formats when one can answer all of the requirements?

I think it’s good to have choice (JPEG-XL and AVIF), but in my opinion it would also be good to have simplicity (1 still image format that developers can use for almost everything).


Chris


From: Leonard Rosenthol <lrosenth@adobe.com<mailto:lrosenth@adobe.com>>
Date: Thursday, November 13, 2025 at 8:08 AM
To: Seeger, Chris (NBCUniversal) <Chris.Seeger@nbcuni.com<mailto:Chris.Seeger@nbcuni.com>>, Chris Blume (ProgramMax) <programmax@gmail.com<mailto:programmax@gmail.com>>, Chris Lilley <chris@w3.org<mailto:chris@w3.org>>
Cc: Portable Network Graphics (PNG) Working Group <public-png@w3.org<mailto:public-png@w3.org>>
Subject: Re: [EXTERNAL] Re: PNG overview slides

Why does it need to be under the W3C umbrella?  We already have JPEG-XL and AVIF that meet those criteria and are supported by most/all browsers.  What would be the benefit/use case for ANOTHER image format?

Leonard

From: Seeger, Chris (NBCUniversal) <Chris.Seeger@nbcuni.com<mailto:Chris.Seeger@nbcuni.com>>
Date: Thursday, November 13, 2025 at 8:04 AM
To: Chris Blume (ProgramMax) <programmax@gmail.com<mailto:programmax@gmail.com>>, Chris Lilley <chris@w3.org<mailto:chris@w3.org>>
Cc: Portable Network Graphics (PNG) Working Group <public-png@w3.org<mailto:public-png@w3.org>>
Subject: Re: [EXTERNAL] Re: PNG overview slides


EXTERNAL: Use caution when clicking on links or opening attachments.


Seems like it would be valuable to get a single image standard to support lossy and lossless under the W3C umbrella.  I’d like to see this move forward.


Chris Seeger

[cid:ii_19a7d69d08d692e332]

[cid:ii_19a7d69d08d5b16b21]


From: Chris Blume (ProgramMax) <programmax@gmail.com<mailto:programmax@gmail.com>>
Date: Thursday, November 13, 2025 at 1:05 AM
To: Chris Lilley <chris@w3.org<mailto:chris@w3.org>>
Cc: Portable Network Graphics (PNG) Working Group <public-png@w3.org<mailto:public-png@w3.org>>
Subject: [EXTERNAL] Re: PNG overview slides

I have also prepared some slides for the 5th Edition roadmap. (I will likely update them further tonight. I want it to feel less "that's asking a lot" and more inspirational.)

I didn't realize there was perhaps a slide design I should follow. :) oh well

https://www.programmax.net/talks/png-5th-edition-roadmap/<https://urldefense.com/v3/__https://www.programmax.net/talks/png-5th-edition-roadmap/__;!!PIZeeW5wscynRQ!teSn4yviUBeJ8O9oZSwfJ9aKO0E-s15YjPBgNu1aE25KBHvIssFohlbOT0_RndqnlcdI20H5N-JmHbdKxCmf$>

On Thu, Nov 13, 2025, 2:56 PM Chris Lilley <chris@w3.org<mailto:chris@w3.org>> wrote:
Slides for an overview of PNG 3rd Edition (plus what we have so far on 4th):

https://www.w3.org/2025/Talks/TPAC/PNG-summary/<https://urldefense.com/v3/__https://www.w3.org/2025/Talks/TPAC/PNG-summary/__;!!PIZeeW5wscynRQ!teSn4yviUBeJ8O9oZSwfJ9aKO0E-s15YjPBgNu1aE25KBHvIssFohlbOT0_RndqnlcdI20H5N-JmHUriXr2b$>

--
Chris Lilley
@svgeesus@mastodon.scot
W3C Distinguished Expert, Color, Graphics & Fonts
W3C Technical Programming Team, Core Web Design