[FFmpeg-trac] #9107(avformat:reopened): ffmpeg can't use RTSP/TCP but OpenRTSP does

[FFmpeg]

#9107: ffmpeg can't use RTSP/TCP but OpenRTSP does
------------------------------------+------------------------------------
             Reporter:  aflopes7    |                    Owner:
                 Type:  defect      |                   Status:  reopened
             Priority:  normal      |                Component:  avformat
              Version:  git-master  |               Resolution:
             Keywords:  rtsp, tcp   |               Blocked By:
             Blocking:              |  Reproduced by developer:  0
Analyzed by developer:  0           |
------------------------------------+------------------------------------
Changes (by aflopes7):

 * status:  closed => reopened
 * resolution:  invalid =>


Comment:

 Well I understand your point more or less.

 I openned this https://stackoverflow.com/q/66280861/1207193 on SO. I
 managed to solve it by modifying `ffmpeg/libavformat/rtsp.c` replacing:

 {{{
 if (!av_strcasecmp(lower_transport, "TCP"))
     th->lower_transport = RTSP_LOWER_TRANSPORT_TCP;
 else
     th->lower_transport = RTSP_LOWER_TRANSPORT_UDP;
 }}}

 by

 {{{
 if (!av_strcasecmp(lower_transport, "TCP") ||
 !av_strcasecmp(lower_transport, ""))
     th->lower_transport = RTSP_LOWER_TRANSPORT_TCP;
 else
     th->lower_transport = RTSP_LOWER_TRANSPORT_UDP;
 }}}

 I insertd `|| !av_strcasecmp(lower_transport, "")` in the code. Making it
 assume that the transport is RTSP_LOWER_TRANSPORT_TCP when lower_transport
 is ommited. This works for me but I wouldn't suggest it as a fix.

 I think would be nice make FFMPEG more forgiving to RTSP servers (not very
 RTSP compliant). Altough I don't know if it would be a accepted behavior
 for FFMPEG team due its current views or approachs.

 In that scenario a better solution would be consider the case of a missing
 lower transport on a rtsp server answer. Then compare with the client-sent
 request to define whether the lower transport was ommitted. And try to
 connect with it.

 I hope I did not take much of your time guys.
 Thank you very much!

--
Ticket URL: <https://trac.ffmpeg.org/ticket/9107#comment:5>
FFmpeg <https://ffmpeg.org>
FFmpeg issue tracker