Combining both canvas capture and device selection

[Oscar Vadillo]

Hi folks,

I am trying to combine both demos the CanvasCapture and the DeviceSelection.

Both of them are working as a charm on the following links:

Canvas Capture: https://janus.conf.meetecho.com/canvas.html

Device Selection: https://janus.conf.meetecho.com/devicetest.html

But, what happens when we try to combine both demos on the same usecase?

For example, by replacing from a canvas capture stream to a device camera or viceversa.

Well, I've tried it on the EchoTest example but it didn't work.

What I did, it was to stablish a communication by using a camera device, and then to inject a stream by using the createOffer method passing a stream generated from the canvas.captureStream() method.

Please find below the screenshots of the result. At first it seems that the renegotiation is OK, but at the end I got the following response: "Janus stopped receiving our video"

Screenshot 1: https://i.imgur.com/vQBqO7v.png

Screenshot 2: https://i.imgur.com/iqhO4CE.png

Any idea what might be going on?

Thanks in advance!

[k meyerhofer]

I ran into a similar situation as you Oscar. I've created a PR to address this issue (here - https://github.com/meetecho/janus-gateway/pull/2604)

Ultimately the user's device camera stream never reaches the `removeTrack` or `addTrack` parts of the janus.js code. If you use my branch to test your use case, you can write the `createOffer` like this:

```

// Assume Janus is correctly initialized

var canvas = document.getElementById('canvas');

var stream = canvas.captureStream();

janusPlugin.createOffer({

  stream: {

    externalStream: stream,

    replaceVideo: true,

  },

  simulcast: false,

  simulcast2: false,

  success: (jsep) => { janusPlugin.send({ message: { request: "configure", audio: true, video: true}, jsep }); },

  error: (error) => { Janus.error('error', error); },

});

```