webrtc.c example doesn't produce video

[Emre Turkay]

Hi all,

I have manually downloaded and compiled Gstreamer 1.15.2 on macos (Mojave 10.14.4).

The tests/examples/webrtc/webrtc.c example of gst-plugins-bad doesn’t produce video while the webrtcbidirectional.c works fine.

Both offer & answer are created but after that I see below suspicious warnings and there is no video output:

(webrtc:27230): GStreamer-WARNING **: 13:49:40.936: gstpad.c:4290:gst_pad_chain_data_unchecked:<dtlssrtpdec0:sink> Got data flow before stream-start event

(webrtc:27230): GStreamer-WARNING **: 13:49:40.936: gstpad.c:4295:gst_pad_chain_data_unchecked:<dtlssrtpdec0:sink> Got data flow before segment event

(webrtc:27230): GStreamer-WARNING **: 13:49:40.962: gstpad.c:4290:gst_pad_chain_data_unchecked:<dtlssrtpdec1:sink> Got data flow before stream-start event

(webrtc:27230): GStreamer-WARNING **: 13:49:40.962: gstpad.c:4295:gst_pad_chain_data_unchecked:<dtlssrtpdec1:sink> Got data flow before segment event

These warnings are not generated by the webrtcbidirectional binary.

Note: I have replaced the “xvimagesink" with “glimagesink” in both files, i.e., 

$ diff webrtc.c.orig webrtc.c
71c71
<       "videoconvert ! queue ! xvimagesink sync=false", TRUE, NULL);
---
>       "videoconvert ! queue ! glimagesink sync=false", TRUE, NULL);

$ diff webrtcbidirectional.c.orig webrtcbidirectional.c
71c71
<       "videoconvert ! queue ! xvimagesink", TRUE, NULL);
---
>       "videoconvert ! queue ! glimagesink", TRUE, NULL);

Basically, I am trying to create a send only and receive only webrtc pair setup but couldn’t succeed so far.

I wonder if this is a bug or something else is missing?

Thanks,

emre