Streaming plugin: Cannot find (rtsp) rtp source stream in incoming rtcp function

General
1

In the janus_streaming_incoming_rtcp() function, searching the GHashTable *media_byid using packet->mindex returns NULL.

void janus_streaming_incoming_rtcp() {
  janus_streaming_rtp_source_stream *stream = g_hash_table_lookup(source->media_byid, GINT_TO_POINTER(packet->mindex));
  if(stream == NULL)
    return;
}

This happens because in the janus_streaming_create_rtsp_source() → janus_streaming_rtsp_connect_to_server() process,
the janus_streaming_rtp_source_stream is created without adding the index to the GHashTable media_byid.

However, in the janus_streaming_create_rtp_source() function, the index is explicitly added to the GHashTable media_byid.

static int janus_streaming_rtsp_connect_to_server() {
  ...
  if(stream->fd[0] != -1)
    g_hash_table_insert(source->media_byfd, GINT_TO_POINTER(stream->fd[0]), stream);
}

Why not insert index in media_byid?
When creating a streaming source with the RTSP type, the processing of incoming RTCP might not be necessary?

2

IIRC we only map RTP, not RTCP. Besides, RTSP mountpoints in the Streaming plugin don’t support more than one audio and one video stream, which means using -1 as a mindex is enough to get it working. Pure RTP mountpoints can have multiple audio and video streams, and so those need to be indexed accordingly to the m-line they’re associated with.

1 Like
4

Lorenzo, Thanks for an answer.
I am one of the people who loves janus.

(My english is not that good.)
I understood. What I wanted to say is …

Big if needed, if include the following REFERENCE code,
the janus_streaming_incoming_rtcp() function can find the stream using mindex and handle the RTCP.

The REFERENCE code is part of the code in the janus_streaming_create_rtp_source() function.

static int janus_streaming_rtsp_connect_to_server(janus_streaming_mountpoint *mp) {
	...

	// *REFERENCE* ->
	/* Map this stream by mindex */
	g_hash_table_insert(live_rtp_source->media_byid, GINT_TO_POINTER(stream->mindex), stream);
	// <- *REFERENCE*

	/* Map this stream by all its file descriptors */
	...
	if(stream->fd[0] != -1)
		g_hash_table_insert(source->media_byfd, GINT_TO_POINTER(stream->fd[0]), stream);
}