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[mediacapture-fromelement] When is the first frame pushed to the MediaStream for captureStream(0)?

From: Philip Jägenstedt via GitHub <sysbot+gh@w3.org>
Date: Thu, 18 Feb 2016 10:19:47 +0000
To: public-media-capture@w3.org
Message-ID: <issues.opened-134537275-1455790783-sysbot+gh@w3.org>
foolip has just created a new issue for 
https://github.com/w3c/mediacapture-fromelement:

== When is the first frame pushed to the MediaStream for 
captureStream(0)? ==
Blink bug:
https://code.google.com/p/chromium/issues/detail?id=587789

Some ad-hoc tests:
http://software.hixie.ch/utilities/js/live-dom-viewer/saved/3896
http://software.hixie.ch/utilities/js/live-dom-viewer/saved/3897

The difference between the two is the order between `captureStream()` 
and `fillRect()`. Firefox and Chrome behave differently; regardless of
 the order Firefox gets the first frame and Chrome does not.

The spec says "A new frame is requested from the canvas when 
`frameCaptureRequested` is true and the canvas is painted" and that 
`frameCaptureRequested` is initially true, but doesn't define "the 
canvas is painted" precisely. It presumably has to do with draw 
commands on `CanvasRenderingContext2D` / `WebGLRenderingContext` and 
not painting of the canvas content on screen.

Please view or discuss this issue at 
https://github.com/w3c/mediacapture-fromelement/issues/29 using your 
GitHub account
Received on Thursday, 18 February 2016 10:19:49 UTC

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