Streamed video not displayed in video grid

[henlamk]

Describe the bug
After starting sharing content via
await meetingManager.audioVideo?.startContentShare(mediaStream)
the video is displayed correctly in the video grid of the user playing the video.
Other participants only get a black screen where the video should be displayed.
However, the sound is being transmitted.

To Reproduce
Steps to reproduce the behavior:

1. Join meeting with more than one user
2. One user starts content share with video

Expected behavior
The video should be displayed in the other participant's video grids.

Desktop (please complete the following information):

• OS: MacOS 11.0.1
• Chrome (89.0.4), Firefox (86.0)
• Chime react lib: 2.1.0, Chime SDK: 2.5.0

[RidipDe]

Hi @henlamk,
Thanks for opening the issue.
Just to double check "Other participants only get a black screen where the video should be displayed." which browser is the participant who turned on the content share on and the participant viewing the black screen using?

You mentioned Chrome and Firefox. So is the issue in Chrome cross Firefox or it occurs in Chrome - Chrome and Firefox - Firefox as well?

Also, how frequently do you encounter the issue?

[henlamk]

I have rechecked just to be sure, and it seems that

• a video played from firefox is displayed perfectly on other browsers
• a video played from chrome is only visible for the playing user himself

This behavior occurs every time.

Thanks for the quick response.

[RidipDe]

I tried to reproduce the issue at my end.

While screen sharing when using the Component Library worked fine in all the following combinations:

• Chrome cross Firefox
• Chrome cross Chrome
• Firefox cross Firefox

However, I was able to repro a similar bug using custom media stream. The behavior seen below is expected in v88 and v89 of Chrome due to an existing bug. The workaround can also be found here.

Steps:

1. User A joins from Firefox (v85)
2. User B joins from Chrome (v88/89.)
3. User A runs the following command in the browser console

const video = document.createElement('video');
video.src = 'https://upload.wikimedia.org/wikipedia/commons/transcoded/c/c0/Big_Buck_Bunny_4K.webm/Big_Buck_Bunny_4K.webm.360p.vp9.webm';
await video.play();
mediaStream = video.mozCaptureStream();
await app.audioVideo?.startContentShare(mediaStream)

4. User B on Chrome sees black screen on the content share video element and no sound is heard.

Can you please confirm if this is what you are observing too?

---

User A on Firefox:

User B on Chrome:

[ltrung]

@henlamk This looks like the issue with Chrome 88+ that has been documented in JS SDK. Could you try disable hardware acceleration to see if it fixes the issue?

[henlamk]

@RidipDe At the point of testing the setup you described it works as previously: playing a video from Firefox to other browsers works fine. The issue I encounter is the other way around, when a chrome user plays a video to other browsers.

@ltrung I have disabled the hardware acceleration and boy oh boy does it work now.

Thanks for looking into this, guys, much appreciated.