webrtcbin cannot "create-offer" while "data-channel" exist

[givip]

Hi everyone!

I write application for video streaming, using Gstreamer and WebRTCBin.

The problem is following:
When I'm trying to "create-offer" first and then establish connection
everything works fine, but
If remote peer already established "data-channel" I cannot "create-offer"
for streaming-channel.

In second case data-channel works well, I can exchange string messages
easily.

I receive assert in function /*sdp_media_from_transceiver*/

/g_assert (trans->mline == -1 || trans->mline == media_idx);/

I really don't understand how it should work.

May be someone can help me



--
Sent from: http://gstreamer-devel.966125.n4.nabble.com/
_______________________________________________
gstreamer-devel mailing list
[hidden email]
https://lists.freedesktop.org/mailman/listinfo/gstreamer-devel

[Matthew Waters]

This sounds like something that may happen.

A reproducible test case would help discern what may be occurring.

Note that if the peer is offerring, one needs to call 'create-answer'
rather than 'create-offer' to complete the negotiation cycle.

If you're attempting renegotiation of the SDP, then that is not
supported in GStreamer 1.14 and only partially supported in 1.16, with
some fixes in master.

Cheers
-Matt

On 11/8/19 4:19 pm, givip wrote:

> Hi everyone!
>
> I write application for video streaming, using Gstreamer and WebRTCBin.
>
> The problem is following:
> When I'm trying to "create-offer" first and then establish connection
> everything works fine, but
> If remote peer already established "data-channel" I cannot "create-offer"
> for streaming-channel.
>
> In second case data-channel works well, I can exchange string messages
> easily.
>
> I receive assert in function /*sdp_media_from_transceiver*/
>
> /g_assert (trans->mline == -1 || trans->mline == media_idx);/
>
> I really don't understand how it should work.
>
> May be someone can help me
>
>
>
> --
> Sent from: http://gstreamer-devel.966125.n4.nabble.com/
> _______________________________________________
> gstreamer-devel mailing list
> [hidden email]
> https://lists.freedesktop.org/mailman/listinfo/gstreamer-devel

_______________________________________________
gstreamer-devel mailing list
[hidden email]
https://lists.freedesktop.org/mailman/listinfo/gstreamer-devel

[givip]

I use Gstreamer 1.17

I don't know how to make an easy reproducible case with signalling server.
Anyway will try.

In this case I received 'offer' for data-channel, I answered with
'create-answer' and data-channel established successfully.

The from peer, which answered I want to establish media-channel and
'create-offer' not working as described.

May be I have todo  'add-transceiver' to add additional connection?




--
Sent from: http://gstreamer-devel.966125.n4.nabble.com/
_______________________________________________
gstreamer-devel mailing list
[hidden email]
https://lists.freedesktop.org/mailman/listinfo/gstreamer-devel

[Matthew Waters]

This sounds like
https://gitlab.freedesktop.org/gstreamer/gst-plugins-bad/merge_requests/428
or a variation thereof.

Cheers
-Matt

On 12/8/19 11:46 pm, givip wrote:

> I use Gstreamer 1.17
>
> I don't know how to make an easy reproducible case with signalling server.
> Anyway will try.
>
> In this case I received 'offer' for data-channel, I answered with
> 'create-answer' and data-channel established successfully.
>
> The from peer, which answered I want to establish media-channel and
> 'create-offer' not working as described.
>
> May be I have todo  'add-transceiver' to add additional connection?
>
>
>
>
> --
> Sent from: http://gstreamer-devel.966125.n4.nabble.com/
> _______________________________________________
> gstreamer-devel mailing list
> [hidden email]
> https://lists.freedesktop.org/mailman/listinfo/gstreamer-devel

_______________________________________________
gstreamer-devel mailing list
[hidden email]
https://lists.freedesktop.org/mailman/listinfo/gstreamer-devel