[foms] Proposal: adaptive streaming using open codecs

Philip Jägenstedt philipj at opera.com
Wed Nov 10 01:19:46 PST 2010

On Tue, 09 Nov 2010 21:48:27 +0100, Chris Pearce <chris at pearce.org.nz>  

> On 9/11/2010 10:22 p.m., Philip Jägenstedt wrote:
>> I still strongly prefer to put the chunking+concatenating in a layer
>> outside of<video>, by extending the suitably named Stream API, see
>> <http://www.whatwg.org/specs/web-apps/current-work/multipage/commands.html#stream-api>.
>> Here's how it might work:
>> var s = new Stream();
>> s.appendURL('chunk1.webm');
>> s.appendURL('chunk2.webm');
>> video.src = s.url;
>> That's it. From the point of view of the video decoder, it's just an
>> infinite stream.
> I'm happy with this idea, provided that chunks can be appended after the
> src is set.

Yes, that's exactly the idea. If you do this...

var s = new Stream();
video.src = s.url;

... then I'd expect a stalled event after 3 seconds and it otherwise  
behaving exactly as if a network request had been started but no data  
received yet.

Implementation-wise, what we'll have to do is some work on the Stream()  
API and then making sure that chained WebM works well. (Actually Ogg could  
be a better fit here, but I'd rather not confuse things by allowing VP8 in  

Philip Jägenstedt
Core Developer
Opera Software

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