Issue 618407 link

Starred by 2 users

Issue metadata

Status:	Assigned
Owner:	m...@chromium.org
Cc:	qiangchen@chromium.org mcasas@chromium.org █ x...@chromium.org mflodman@chromium.org guidou@chromium.org mfo...@chromium.org sprang@chromium.org niklase@chromium.org brandtr@chromium.org m...@chromium.org terelius@chromium.org taku...@chromium.org powerb@chromium.org holmer@chromium.org
Components:	Blink>GetUserMedia>Desktop Blink>GetUserMedia>Tab Blink>MediaStream>CaptureFromElement Blink>WebRTC>Video Internals>Cast>Streaming Internals>Media>ScreenCapture
EstimatedDays:	----
NextAction:	----
OS:	All
Pri:	2
Type:	Bug

Blocked on:
issue 806366

Screen capturers don't set VideoFrame timestamp and REFERENCE_TIME correctly

Project Member Reported by m...@chromium.org, Jun 8 2016

Issue description

When reviewing a recent code change (https://codereview.chromium.org/2045813003/), it became obvious that the screen capturers are not setting the timestamp fields correctly. This needs to be fixed.

Furthermore, we need to evaluate whether downstream consumers (e.g., Cast Streaming, WebRTC, Media Element Capture, etc.) are operating on the timing information correctly. It's likely this work would help to improve A/V sync performance tests in the waterfall.

Comment 1 by mcasas@chromium.org, Jun 21 2016

Status: Assigned (was: Available)

Comment 2 by qiangchen@chromium.org, Jun 21 2016

Cc: mcasas@chromium.org

Any detail?

I think at [1] we pass the REFERENCE_TIME and timestamp into OnIncomingCapturedData, which I cannot see an error.

[1]https://cs.chromium.org/chromium/src/content/browser/media/capture/desktop_capture_device.cc?sq=package:chromium&l=317

Comment 3 by x...@chromium.org, Jul 14 2016

Cc: x...@chromium.org

I think we do set the REFERENCE_TIME, but not the timestamp in ThreadSafeCaptureOracle::DidCaptureFrame(). 

We might just set the difference between current |reference_time| and the first seen |reference_time| as the timestamp for successively captured frames. 

Yuri, does this sgty? If yes, I can go ahead with this fix.