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Comment by yoz-y | Hacker News Reader

I wonder. Could something like this be packaged as an extension and thus enable javascript-powered codecs for browsers that do not have the full set? (webm for Safari comes to mind)

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This is a little different than codec support, though as other replies indicate, that can be done too. This is just demuxing the stream in one format, re-muxing it in a different format, and feeding it into <video> to actually do the decoding and playback.

On the other hand, something like https://github.com/brion/ogv.js/ is actually doing all of the decoding and playback in JavaScript/asm.js, using C libraries compiled with Emscripten.

Anyhow, yes, it probably would be possible to package up extensions that would apply one of these automatically to <video> tags with unsupported codecs or container formats. It's just a simple matter of programming.

A similar idea, HLS.js [0], allows playback of HLS on platforms that do not support it natively. Open-sourced by Dailymotion, it is used by The NYTime [1] amongst others to reduce the number of video renditions they have to produce for each video.

[0] https://github.com/dailymotion/hls.js

[1] http://open.blogs.nytimes.com/2016/02/08/flash-free-video-in...

Yes, in fact it's even deployed on Wikipedia: https://github.com/brion/ogv.js/

Seriously, the contributions of Brion Vibber to the world are completely undersung.

However, isn't this server side and not clientside?

Nope, it's a clientside "polyfill of <video>", basically. Try out the demo in the page - it does all playback in Javascript and WebGL.

Brion gave a talk about this just a few weeks ago: https://www.twitch.tv/demuxed/v/94956075

Yes, it is possible. However, note that webm on safari will require transcoding vp8/vp9 into h.264. This is much more compute intensive than just transmuxing a flv (which has to be in h.264/aac) into another container (in this case fragmented mp4).

Here is an example of playing HEVC with this method: https://strukturag.github.io/libde265.js/

Broadway.js is Android's H.264 decoder compiled with Emscripten to JavaScript:

https://github.com/mbebenita/Broadway

http://mbebenita.github.io/Broadway/foxDemo.html

Or maybe even include the wasm codec/player along with the video. Then it doesn't matter what the platform supports as long as it can run wasm.

Wasm does not solve problem of hardware acceleration completely. Wasm reduces recompilation time on client side, which is not a big deal in this case.

I was seriously just thinking that.

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