Re: Blob URLs for MediaStreams

On 10/9/2012 8:51 AM, Robert O'Callahan wrote:
> On Wed, Oct 10, 2012 at 1:45 AM, Harald Alvestrand 
> <harald@alvestrand.no <mailto:harald@alvestrand.no>> wrote:
>
>     On 10/09/2012 09:49 AM, Cyril Concolato wrote:
>
>         Le 10/9/2012 7:26 AM, Robert O'Callahan a écrit :
>
>             http://dev.w3.org/2011/webrtc/editor/getusermedia.html#methods-1
>             The current draft says that createObjectURL mints a Blob
>             URL for a MediaStream. I don't think that is a good idea,
>             since Blobs are static objects (an immutable array of
>             bytes), and MediaStreams are a constantly-changing stream
>             of media data. So a URL constructed for a MediaStream
>             cannot be used everywhere a Blob could be used, for
>             example it can't be loaded via XmlHttpRequest.
>
>     I agree - the Blob URL here is very much used as "opaque token
>     passed from one API to another", not as "first-class object you
>     can actually do things with".
>     Mozilla's argued before that the use of "getURL(stream)" is not
>     appropriate, and we should instead define a "srcObject" attribute
>     on the HTML media elements - but this spec hasn't landed yet.
>
>
> I still argue that, but as long as createObjectURL is around we should 
> make it work as well as possible :-).

I'll note since Rob didn't mention it that Mozilla's current nightlies 
and (in a day or so) Aurora (FF18) have video.mozSrcObject = stream 
support, and we've dropped support for video.src = stream.

-- 
Randell Jesup
randell-ietf@jesup.org