Re: [mediacapture-record] ignoreMutedMedia on a combination of muted and unmuted tracks?

I'm not sure about what was the original intention of the Spec, or the
 status of the Media Capture and Streams at the time... 

But I replied to @alvestrand in the PR with an example that might 
clarify your questions; the hypothetical case was `if track A is 
recorded and track B is muted for 10 seconds with 
ignoreMutedMedia=true, will they then be 10 seconds out of sync?`:
> Every recorded video frame has a timestamp associated, if there is a
 jump in any of the sequences of timestamps, any player would just 
keep the last drawn canvas, unless, that is, ignoreMutedMedia inserts 
black video frames.
> 
> In the hypothetical case you mention, assuming A and B are video 
tracks for simplicity, after the muted hiatus in track B, they'll 
still be in sync, because the UA will still produce correct timestamps
 in the container. If you were playing both in parallel, then A will 
play all the way with no hiccups, whereas B will either be frozen for 
10 seconds, or turn black for ten seconds, depending on 
ignoreMutedMedia.
>
> I'm not sure about the extent of enabled versus muted. In Chrome, 
muted is a reflection of no video passing by the track during a 
certain period of time; this being affected by enabled or not, depends
 on where the video flow is interrupted (before or after the Track). 
Maybe @guidou knows more?





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Received on Wednesday, 14 December 2016 23:41:57 UTC