Screen sharing from android app to browser on self-hosted instance does not work

newton1 · November 18, 2020, 11:06pm

Hi,

latest beta of android app does support screen sharing - great!

If I’m in a meeting on a self hosted jitsi instance with two android devices, screen sharing from android app works - can see the screen content on the other android device.
If I join that meeting with a browser (firefox, linux) screen sharing stops to work. If I leave the meeting with the browser attendee screen sharing to the other android device starts to work again.

If I do the same thing in a meeting on meet.jit.si that works - screen sharing stays functional when I join with the same browser and I can see the shared screen content also in the browser.

So, I think there must be something different between the instance on meet.jit.si and my self hosted instance - but I’ve no idea, what that might be. I upgraded my instance to nightly - did’nt change anything.

Any ideas?

Thanks.

damencho · November 18, 2020, 11:15pm

I suspect that if you open 3 browser tabs in the same URL on your deployment you will not have video, but with 2 yes. If so, check the advanced section of https://jitsi.org/qi

newton1 · November 18, 2020, 11:26pm

Nope. I can open 3 or even 4 (did not try even more) tabs in the same browser on the same url on my server and I have video in all of them.

If I understood correctly, the advanced setup is needed if the server is behind NAT - this is not the case, it has a public ip.

damencho · November 18, 2020, 11:54pm

Hum that is strange …

emrah · November 19, 2020, 6:05am

It seems that the android devices work on P2P mode. Could you test it with 3 android devices

newton1 · November 19, 2020, 7:51pm

OK, tested with 2x android hw and 1x emulator - indeed does not work on my server. But does work on meet.jit.si - what do I need to change on my server to make it work there also?

emrah · November 19, 2020, 8:03pm

If this server is in your local network and the desktop clients are in your local network too, probably you have an unaccessable UDP/10000 problem

newton1 · November 19, 2020, 9:03pm

No. Server is in a datacenter and desktop clients are at home. I can see traffic on port 10000 udp in tcpdump.

I forgot to tell, that only screen sharing does not work. When I use the camera on the android device, this works.

Sander · November 22, 2020, 6:35pm

Have the same issue. My self-hosted Jitsi instance is working fine, also with 3 and more participant (incl. video). Would like to use screen sharing from Android as well. When I use meet.jit.si this works fine (have tested between two Android phones connected to the meeting. However, on my own instance as soon as one device starts screen sharing, on the receiving phone the video disappears, but the screen just goes gray-ish. As soon as the screen sharing is deactivated, video is shown again. Any ideas why it might not work on my own (up-to-date) instance?

OlegZ · December 6, 2020, 4:17am

It’s my problem too!

OlegZ · December 8, 2020, 2:29am

Is it possible to get the info about desktop sharing working site meet.jit.si configs?
I hope, it’s solving.

alan_tulais · December 9, 2020, 5:31pm

@OlegZ It can be found at: https://meet.jit.si/config.js

In the other hand, I’m facing the same issue. Camera works fine with 3+ participants, but desktop sharing on android is not (on our server, if we target at jitsi meet servers it works just fine). @damencho Do you know if jvb must be updated in order to make it work?

Regards

ashok-ai · December 13, 2020, 3:39am

HI @alan_tulais, are you able to get this screen share working from your android to desktop? We are also facing the same issue. Any help is much appreciated. Thanks

alan_tulais · December 17, 2020, 9:59pm

@ashok-ai @damencho @newton1 After some research, I had to patch react-native-webrtc library in order to make it work.

Changing the following line of code while creating the videotrack:

github.com

react-native-webrtc/react-native-webrtc/blob/master/android/src/main/java/com/oney/WebRTCModule/GetUserMediaImpl.java#L344


PeerConnectionFactory pcFactory = webRTCModule.mFactory;
EglBase.Context eglContext = EglUtils.getRootEglBaseContext();
SurfaceTextureHelper surfaceTextureHelper =
    SurfaceTextureHelper.create("CaptureThread", eglContext);
if (surfaceTextureHelper == null) {
    Log.d(TAG, "Error creating SurfaceTextureHelper");
    return null;
}
VideoSource videoSource = pcFactory.createVideoSource(videoCapturer.isScreencast());
videoCapturer.initialize(surfaceTextureHelper, reactContext, videoSource.getCapturerObserver());
String id = UUID.randomUUID().toString();
VideoTrack track = pcFactory.createVideoTrack(id, videoSource);
track.setEnabled(true);
tracks.put(id, new TrackPrivate(track, videoSource, videoCaptureController));
videoCaptureController.startCapture();

With this:

VideoSource videoSource = pcFactory.createVideoSource(false);

Did the trick. To be honest, I would like to know why it didn’t work before this change. After reviewing the following commit from another implementation that worked well with more than three participants:

I found this comment:

So I tried and it worked. I guess It works well on jitsi meet servers because they are configured as MCU.

I would like to know if this could have any side effect or why does it works only in MCU mode.

Regards

GibraanJafar · January 1, 2021, 7:30am

Thanks @alan_tulais. This is just the solution I needed to make it work on my end. Thanks a ton again for this post.

ayu · January 2, 2021, 7:01pm

Hi @alan_tulais,

I had to create an account to thank you for this. Thanks a lot. While we wait for an official response or fix, this works!

Regards,

alan_tulais · January 6, 2021, 1:20pm

@GibraanJafar @ayu You’re welcome I’m glad to hear it was useful. @saghul Any chance we can include this in the original repo (actually I also added a flag, if the function call is for the camera device it uses boolean value from “videoSource.isScreencast()” method, otherwise it just uses “false”)?.

I also found this recent commit, I don’t know if it had any effect on this:

Thank you!

Sander · April 1, 2021, 1:10pm

Hi,

this still does not seems to work out of the box. Do not know where and how exactly to make the changes manually. Can someone point me in the right direction? Thanks a lot in advance.