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A new PNG spec

(www.programmax.net)
614 points bluedel | 1 comments | 24 Jun 25 13:01 UTC | HN request time: 0s | source
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tonyedgecombe ◴[25 Jun 25 06:36 UTC] No.44374207[source]▶
>After 20 years of stagnation, PNG is back with renewed vigor!

After 20 years of success, we can't resist the temptation to mess with what works.

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encom ◴[25 Jun 25 07:22 UTC] No.44374493[source]▶
Yea I'm mildly concerned about this as well. PNG's age is a feature, in a time where software development has gone to hell.
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HelloNurse ◴[25 Jun 25 07:30 UTC] No.44374548[source]▶
Without the new HDR and color profile handling, PNG was still useful but significantly obsolete. Display hardware has progressed over a few decades, raising the bar for image files.
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leni536 ◴[25 Jun 25 08:07 UTC] No.44374778[source]▶
PNG already supports color profiles, but probably not HDR. I would say that the gamut argument in the article is misleading, you can already encode a wider gamut.

Not sure how HDR encoding works, but my impression is that you can set a nominal white point other than (1, 1, 1) in your specified colorspace. This is an extension, but orthogonal to specifying the colorspace itself and the gamut.

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1. ProgramMax ◴[25 Jun 25 18:09 UTC] No.44380218{3}[source]▶
You are correct. I designed the article to be very approachable and understandable for the normal person. As such, I took some liberties like only showing HDR primaries and ignoring transfer function. I linked to Chris Lilley's post to give experts a more correct answer.

But wide color gamut was already possibly in PNG via ICC profiles (HDR was not). And those primaries I showed could have been used in a wide color image.

So the image is a bit misleading or red-flag-y to experts who know. But to the average person, I think it is as truthful as I can be without getting too deep in the weeds.