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Comment by emerged | Hacker News Reader

Do you suggest that the untold billions of both animated and static GIFs should be lossily transcoded to mp4 (which presumably also has a limited shelf life?) so that we can finally remove GIF support from web browsers because [reason here]?

Btw, mp4 is a container format.

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There is also APNG, which might be better suited for this and supports transparency.

APNG is a strictly superior drop in replacement for GIF, has been around for ages, but never got adopted by anyone but firefox. I don't get it. Animated WebP also fills the same role but lacks support outside of Chrome.

The trend of converting gifs to h264 videos is kind of awful in terms of image quality but I'm sure it saves a lot of bandwidth for sites like imgur and twitter.

APNG works in both Chrome and Safari, haven't tested in IE/Edge.

h264 might have an advantage since it does consume less cpu due to hardware support though.

aPNG was never accepted by the PNG standards body, and tends to be as large or larger than GIF[1]. If we're going to go through the effort of converting, then WebP makes way more sense.

1. https://www.androidpolice.com/2017/05/01/animated-png-format...

If you convert static GIF to static PNG, 99% of the time you'll get a smaller file. That was the original goal of PNG project, and it succeeded: static GIFs disappeared completely. Converting animated GIF to animated PNG leads to similar filesize savings.

Video formats like webp exploit temporal and spatial similarities to get efficiency. Gif/apng do not. This reduces bandwidth costs and file sizes very much.

Download a dozen random GIF cinemagraphs, and try gif2webp and gif2apng on them.

Try ffmpeg or vlc instead, you will get much better results. Ffmpeg has support for almost all video/audio formats ever invented.

It seems to me that WebP is more of a replacement for "animated" JPEG than PNG. http://littlesvr.ca/apng/gif_apng_webp5.html in these comparisons apng has the edge. Ideally we could have both. Sadly Apple is not willing to add webp/webm support to safari.

You're right, looks like Chrome added it last year, only 9 years after Firefox. h264 is efficient to decode but it's always lossy and gif->h264 conversions have the worst of both worlds qualities of h264 video compression artifacts and being limited to a 256 color palette.

most normal people consuming the content don’t care about it being lossy as PSNR good. That’s the reason why Giphy and others provide an mp4/264 alternate format. Reddit also seems to be embedding mp4/264 instead of gifs.

I can not believe nobody mentioned:

APNG is (can be?) lossless. You have to lose a lot of quality in GIF to get reasonable filesizes. APNG gets you lossless quality with decent sizes.

Quality sticklers rejoice!

APNG's palette mode is much worse than GIF, and RGBA mode has 3-4 times more data to compress. Deflate is better than LZW, but not that much better, so APNG can only offer either worse quality or worse file size.

Lots of large GIFs used today were converted from H.264 (YouTube, etc.), so the crap quality of H.264 -> GIF -> H.264 is entirely the fault of GIF.

> APNG's palette mode is much worse than GIF

In terms of image quality, it's only slightly worse. But having the same palette for all frames helps to make inter-frame optimization much more efficient.

Post is talking about lossy gif->gif conversion. MP4/H264 do the same but get you 10x gains, while maintaining much better quality. One tradeoff is the loss of transparency.

Yes, I assumed everyone here knows about mp4/h264/etc. Nokia also released a more formal container spec using HEIF, that supports transparency (most folks will complain about patent encumbered issues). However it will be a while before browsers support it.

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