Why won't VLC send an rtsp PLAY request to my server? - tcp

Question

I'm implementing an RTSP server in NodeJs, using the RFC's (rtsp, rtp, sdp) and this tutorial.
I'm using VLC to test my implementation, and it works fine for the example (link at the bottom of the tutorial) but stops halfway for my server.
I'm suspecting some RFC compliance issue, but I can't find it, and VLC isn't really providing any useful information as to what it's doing.
Running wireshark and the c++ server implementation, and pointing VLC to it shows all the steps:
OPTIONS rtsp://192.168.10.151:8554/mjpeg/1 RTSP/1.0
CSeq: 2
User-Agent: LibVLC/2.2.1 (LIVE555 Streaming Media v2014.07.25)
RTSP/1.0 200 OK
CSeq: 2
Public: DESCRIBE, SETUP, TEARDOWN, PLAY, PAUSE
DESCRIBE rtsp://192.168.10.151:8554/mjpeg/1 RTSP/1.0
CSeq: 3
User-Agent: LibVLC/2.2.1 (LIVE555 Streaming Media v2014.07.25)
Accept: application/sdp
RTSP/1.0 200 OK
CSeq: 3
This should be date
Content-Base: rtsp://192.168.10.151:8554/mjpeg/1/
Content-Type: application/sdp
Content-Length: 90
v=0
o=- 6334 1 IN IP4 192.168.10.151
s=
t=0 0
m=video 0 RTP/AVP 26
c=IN IP4 0.0.0.0
SETUP rtsp://192.168.10.151:8554/mjpeg/1/ RTSP/1.0
CSeq: 4
User-Agent: LibVLC/2.2.1 (LIVE555 Streaming Media v2014.07.25)
Transport: RTP/AVP/TCP;unicast;interleaved=0-1
RTSP/1.0 200 OK
CSeq: 4
This should be date
Transport: RTP/AVP/TCP;unicast;interleaved=0-1
Session: -2144778205
PLAY rtsp://192.168.10.151:8554/mjpeg/1/ RTSP/1.0
CSeq: 5
User-Agent: LibVLC/2.2.1 (LIVE555 Streaming Media v2014.07.25)
Session: -2144778205
Range: npt=0.000-
RTSP/1.0 200 OK
CSeq: 5
This should be date
Range: npt=0.000-
Session: -2144778205
RTP-Info: url=rtsp://127.0.0.1:8554/mjpeg/1/track1
And the VLC messages:
...
live555 debug: RTP subsession 'video/JPEG'
core debug: selecting program id=0
live555 debug: setup start: 0.000000 stop:0.000000
live555 debug: play start: 0.000000 stop:0.000000
core debug: using access_demux module "live555"
core debug: looking for decoder module matching "any": 43 candidates
...
When I run my own server, it never sends the play request:
OPTIONS rtsp://rasmus.axit.local:8554/mjpeg/1 RTSP/1.0
CSeq: 2
User-Agent: LibVLC/2.2.1 (LIVE555 Streaming Media v2014.07.25)
RTSP/1.0 200 OK
CSeq: 2
Public: DESCRIBE, SETUP, TEARDOWN, PLAY, PAUSE
DESCRIBE rtsp://rasmus.axit.local:8554/mjpeg/1 RTSP/1.0
CSeq: 3
User-Agent: LibVLC/2.2.1 (LIVE555 Streaming Media v2014.07.25)
Accept: application/sdp
RTSP/1.0 200 OK
CSeq: 3
Date: Fri, 09 Sep 2016 09:36:29 GMT
Content-Base: rtsp://rasmus.axit.local:8554/mjpeg/1
Content-Type: application/sdp
Content-Length: 91
v=0
o=- -12345678 1 IN IP4 192.168.10.71
s=
t=0 0
m=video 0 RTP/AVP 26
c=IN IP4 0.0.0.0
SETUP rtsp://rasmus.axit.local:8554/mjpeg/1/ RTSP/1.0
CSeq: 4
User-Agent: LibVLC/2.2.1 (LIVE555 Streaming Media v2014.07.25)
Transport: RTP/AVP/TCP;unicast;interleaved=0-1
RTSP/1.0 200 OK
CSeq: 4
Date: Fri, 09 Sep 2016 09:36:29 GMT
Transport: RTP/AVP/TCP;unicast;interleaved=0-1
Session: -12345678
And VLC:
...
live555 debug: RTP subsession 'video/JPEG'
It doesn't continue from there.
I can't figure out what it's missing. Earlier it didn't send a SETUP either, and that turned out to be a missing empty line on the DESCRIBE response. Consequently I've tried adding various amount of newlines, ids, different dates and what not in different places, but no dice.
Please let me know if you need more information.

Answer 1

Your response to the DESCRIBE commands seems to be invalid - you are replying with 96 characters while the Content-Length header states 91. Not sure if this affects the outcome, but I assume VLC could fail because of this (it could be that it cannot parse the connection data line). Also there seems to be an unneeded extra newline at the end of the SDP data at the end of the last line.