[Webkit-unassigned] [Bug 181663] Video Element cannot playback local Canvas.captureStream on iOS

[bugzilla-daemon at webkit.org]

https://bugs.webkit.org/show_bug.cgi?id=181663

Frank Robert <jroberfr at twitch.tv> changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
                 CC|                            |jroberfr at twitch.tv

--- Comment #15 from Frank Robert <jroberfr at twitch.tv> ---
It seems that this is still reproducible in Safari on Mac (as well as on iOS).

> Safari Version 15.2 (16612.3.6.1.8, 16612)
> Mac Version 11.6.2 (20G314)

Here are a few links to repro:

• https://www.demo2s.com/javascript/javascript-canvas-change-play-out-delay-in-webrtc-stream.html
• https://webkit.org/blog-files/webrtc/pc-with-effects/index.html
• https://webrtc.github.io/samples/src/content/capture/canvas-video/

Bonus, here's a reproducible related bug for MSE canvas captures to video:
• https://s3.amazonaws.com/storage2.interlude.fm/dev_temp/tomer/safari_mse_canvas_bug/index.html

Interestingly, in the `webrtc.github.io` example, they use WebGL and I've noticed that occasionally (1 in every ~10 refreshes _) you will get what appears to be the first frame drawn correctly from `captureStream`. This is supported by the Limitations & Additional Functionality section of the CaptureStream implementation spec sheet https://docs.google.com/document/d/1JmWfOtUP6ZqsYJ--U8y0OtHkBt-VyjX4N-JqIjb1t78/edit#heading=h.hkgqgoi0quq2 wherein they describe the background/alpha channel as being drawn with black pixels. 

When that happens a `drag` (possibly something else/similar) event on the canvas or video element seem to trigger a proper redraw of the video element and the video "plays". The caveat to this approach is that I've yet to be able to programmatically trigger the drag event to redraw.

-- 
You are receiving this mail because:
You are the assignee for the bug.
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://lists.webkit.org/pipermail/webkit-unassigned/attachments/20220120/990d9189/attachment-0001.htm>