Re: [media-source] ISO BMFF bytestream: how can CEA 608 / 708 embedding be supported?

Matt,

I replied @ https://github.com/w3c/media-source/issues/58


Bob


On 3/22/16, 4:12 PM, "wolenetz via GitHub" <sysbot+gh@w3.org> wrote:

>wolenetz has just created a new issue for 
>https://github.com/w3c/media-source:

>
>== ISO BMFF bytestream: how can CEA 608 / 708 embedding be supported? 
>==
>If I understand correctly, CEA 608 / 708 embedding of text track data 
>is one option for sourcing text track data described within 
>https://dev.w3.org/html5/html-sourcing-inband-tracks/#mpeg4
>However, such embedding/signalling of the embedding occurs after the 
>ISO BMFF initialization segment.
>Since track types and counts must remain consistent across 
>initialization segments for a SourceBuffer, and the initialization 
>segment received algorithm is the sole place in MSE where various 
>track attributes (like SourceBuffer.TextTracks and 
>HTMLMediaElements.TextTracks) are populated, is it impossible to 
>support CEA 608 / 708 embedding of text track data in ISO BMFF in any 
>compliant MSE implementation?
>
>@silviapfeiffer : Am I missing some part of signalling for CEA 608 / 
>708 in ISO BMFF that actually occurs within an MSE initialization 
>segment?
>
>@jdsmith3000 / @mwatson2 / other MSE user agent implementors: Do you 
>have this working somehow? Does the MSE ISO-BMFF bytestream spec 
>and/or https://dev.w3.org/html5/html-sourcing-inband-tracks/#mpeg4 
>need some update, or am I indeed missing some simple signalling within
> the defined MSE ISO BMFF initialization segment which allows such 
>embedded text tracks to be known at the time of executing the 
>initialization segment received algorithm?
>
>Please view or discuss this issue at 
>https://github.com/w3c/media-source/issues/58 using your GitHub 
>account
>

Received on Tuesday, 22 March 2016 22:41:55 UTC