[asterisk-dev] WebRTC SFU: support add video track dynamically

[Joshua C. Colp]

On Wed, May 8, 2019, at 1:26 PM, Xiemin Chen wrote:
> Please see the comments in the following codes, at the moment, A & B 
> both have one audio & video stream separately and B is starting to add 
> an extra sharing video:

<snip>

> 
> /* The stream count of B's active_media_state->topology is 3, one B's 
> audio, one B's video, one A's video with name softbridge_dest_PJSIP... 
>  The sdp->media_count is 3, one for audio, one for camera video, one 
> for sharing video
>  Here B's sharing video is map to A's video with name 
> softbridge_dest_PJSIP... */

So are you adding a stream or replacing a stream? If adding I would expect 4 streams in the SDP media count: Audio, camera video, A's video, and the new sharing video. Are you actually instead replacing/reusing an existing stream?

<snip>

> 
> /* If the code of B's new sharing video stream executes here, does it 
> need to call set_mid_and_bundle_group() & 
> set_remote_mslabel_and_stream_group() 
>  & handler->negotiate_incoming_sdp_stream for the new stream setup 
> instead of the handler->defer_incoming_sdp_stream()?
>  */

The purpose of this function is for determining if the SDP handling should be deferred until a later time, it's not for actually performing the SDP negotiation. That is done elsewhere. I don't believe this function should have any of the above done in it.

-- 
Joshua C. Colp
Digium - A Sangoma Company | Senior Software Developer
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