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• Anomalie #3436 (Nouveau) : Forum : id_thread = 0

  5 mai 2015, par Debondt Didier

  Si j’utilise l’API objet pour créer des éléments de forum, sans spécifier explicitement un id_thread :

  $id_forum = objet_inserer(’forum’, null, $c) ;
  

  Il est possible que le champ id_thread soit égale à 0. Hors cela ne devrait jamais être le cas, il devrait à minima être égale à id_forum.

• Using ffplay with RTSP and source-specific multicast

  14 septembre 2022, par bigbrobrody

  We are trying to use ffplay to join a live video source in a network that uses IGMPv3 source-specific multicast.

  


  If we use an SDP file this works fine and wireshark shows that ffplay correctly sends a source-specific multicast membership report.

  


  However, when we try to join the same source using RTSP, ffplay seems to ignore the source-specific address contained in the SDP response to RTSP DESCRIBE and fails because it tries to join for any source. This is the command used :

  


  ffplay -loglevel debug -rtsp_transport udp_multicast -protocol_whitelist rtp,udp,tcp -i rtsp://[username:password]@[ip address]/stream0

  


  The SDP response as reported by ffplay includes :

  


  a=source-filter: incl IN IP4 * [ssm ip address]

  


  The only error reported by ffplay is :

  


  Failed to parse interval end specification ''

  


  Wireshark shows that ffplay is not performing an SSM join :

  


  Membership Report / Join group [group IP address] for any sources

  


  Further details in the screenshot below. Are we doing something wrong, is this a feature of ffplay or a potential bug ?

  


  I note that libavformat/rtsp.h contains the comment /** The following are used only in SDP, not RTSP */ against code for sdp port, source-specific multicast addresses, etc. I’m not sure if that hints at our issue being because of a feature in ffmpeg.

  


  ffplay using rtsp and ssm

  


• using ffmpeg to convert a mkv or mp4 suitable for a DVD player that supports MPEG-4 / DivX [closed]

  17 juillet 2022, par Neil Telford

  I got a DVD Player with USB support. It is a recent player (DVD-225), but the documentation is sparse, but it does claim MPEG-4 and DivX support.

  


  Now, I have got certain AVI files to play via USB, but everything else fails. I looked at the metadata of an AVI file that worked via ffprobe, and got the following :

  


  Metadata:
    encoder         : Lavf58.17.101   Duration: 00:58:30.94, start: 0.000000, bitrate: 1336 kb/s
    Stream #0:0: Video: mpeg4 (Simple Profile) (xvid / 0x64697678), yuv420p, 640x290 [SAR 1:1 DAR 64:29], 1196 kb/s, 23.98 fps, 23.98 tbr,
23.98 tbn, 23.98 tbc
    Stream #0:1: Audio: mp3 (U[0][0][0] / 0x0055), 48000 Hz, stereo, fltp, 128 kb/s


  


  Now, I figured that if I can replicate the above, I can convert most things to play via USB, even if it isn't the most up to date codecs.

  


  I've tried various combinations, but they all fail. The closest I got was by using the following shell script :

  


  for i in *.avi; do ffmpeg -i "$i" -c:v mpeg4 -vtag divx -qscale:v 3 -c:a libmp3lame -qscale:a 4 "_${i%.*}.avi"; done


  


  This has a strange result that it will play the audio track, but not the video track. The metadata I got from this was :

  


  Metadata:
    encoder         : Lavf58.45.100
  Duration: 00:58:07.99, start: 0.000000, bitrate: 3026 kb/s
    Stream #0:0: Video: mpeg4 (Simple Profile) (divx / 0x78766964), yuv420p, 1280x720 [SAR 3:4 DAR 4:3], 2901 kb/s, 23.98 fps, 23.98 tbr, 23.98 tbn, 24k tbc
    Metadata:
      title           : ******************
    Stream #0:1: Audio: mp3 (U[0][0][0] / 0x0055), 48000 Hz, stereo, fltp, 109 kb/s
    Metadata:
      title           : ******************


  


  Does anyone know where I am going wrong with this ? I've converted AVI, MKV and MP4 files, and while they work on my computer, the DVD player seems to be very picky.

  


  Any suggestions ?

  


  Thanks
Neil