Last modified: 2014-05-23 01:27:55 UTC
Lots of users (essentially, anyone who uses a browser other than Firefox) have browsers that don't support APNG files. Instead, their browser will interpret it as a regular PNG file and just show the first frame. A nicer failure mode would be to give everyone a GIF file instead, and then at runtime use some client-side JS to sniff for the feature and if present replace the GIF with the APNG instead.
For reference, example apng file: https://en.wikipedia.org/wiki/File:Animated_PNG_example_bouncing_beach_ball.png ----- Would probably require new software deployed to server (I don't think image magick supports apng->gif, but not sure). Googling suggests http://apng2gif.sourceforge.net/
Note the general problem with APNG->GIF is that you may have to apply two lossy transformations: * color quantization to an 8-bit palette, probably with dithering * 8 or 16-bit alpha channel -> 1-bit alpha channel Both of these will potentially leave a GIF version looking like crap, and most people will get the crappy version. :( I'd kinda prefer to phase out animated GIF in favor of proper video formats, editable slideshows of static images, or animated SVG... introducing APNG basically just gives us a slightly better animated GIF exclusively for Firefox users.
lowering priority in light of comment 2. Possible wontfix
(In reply to Brion Vibber from comment #2) > I'd kinda prefer to phase out animated GIF in favor of proper video formats, > editable slideshows of static images, or animated SVG... That's a nice theory, but it's highly unlikely to actually happen given the low uptake in the toolchain; APNG isn't widely used either, but ASVG is almost unknown IME. > introducing APNG basically just gives us a slightly better animated > GIF exclusively for Firefox users. Firefox users and those who care about these things and so have browser plugins/etc. :-) But yeah.