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A new PNG spec

(www.programmax.net)
618 points bluedel | 2 comments | 24 Jun 25 13:01 UTC | HN request time: 0.513s | source
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ProgramMax ◴[25 Jun 25 19:00 UTC] No.44380761[source]▶
Author here. Hello everyone! Feel free to ask me anything. I'll go ahead and dispel some doubts I already see here:

- It isn't really a "new format". It's an update to the existing format. - It is very backwards compatible. -- Old programs will load new PNGs to the best of their capability. A user will still know "that is a picture of a red apple".

There also seems to be some confusion about how PNGs work internally. Short and sweet: - There are chunks of data. -- Chunks have a name, which says what data it contains. A program can skip a chunk it doesn't recognize. - There is only one image stream.

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1. nabla9 ◴[26 Jun 25 12:18 UTC] No.44386681[source]▶
Does it have any advantage over Lossless encoding in JPEG XL?
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2. ProgramMax ◴[26 Jun 25 19:26 UTC] No.44390466[source]▶
Yes, lots.

The big one is adoption. I love JPEG XL and hope it becomes more widely adopted. It is very scary to add a format to a browser because you can never remove it. Photoshop and MSPaint no longer support ICO files, but browsers do. So it makes sense for browsers to add support last, after it is clearly universal. I think JPEG XL is well on their way using this approach. But they aren't there yet and PNG is.

There is also longevity and staying power. I can grab an ancient version of Photoshop off eBay and it'll support PNG. This also benefits archivists.

As a quick side note on that: I want people to think about their storage and bandwidth. Have they ever hit storage/bandwidth limits? If so, were PNGs the cause? Was their site slow to load because of PNGs? I think we battle on file size as an old habit from the '90s image compression wars. Back then, we wanted pixels on the screen quickly. The slow image loads were noticeable on dial-up. So file size was actually important then. But today?? We're being penny-wise and pound-foolish.