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  • Des sites réalisés avec MediaSPIP

    2 mai 2011, par

    Cette page présente quelques-uns des sites fonctionnant sous MediaSPIP.
    Vous pouvez bien entendu ajouter le votre grâce au formulaire en bas de page.

  • HTML5 audio and video support

    13 avril 2011, par

    MediaSPIP uses HTML5 video and audio tags to play multimedia files, taking advantage of the latest W3C innovations supported by modern browsers.
    The MediaSPIP player used has been created specifically for MediaSPIP and can be easily adapted to fit in with a specific theme.
    For older browsers the Flowplayer flash fallback is used.
    MediaSPIP allows for media playback on major mobile platforms with the above (...)

  • De l’upload à la vidéo finale [version standalone]

    31 janvier 2010, par

    Le chemin d’un document audio ou vidéo dans SPIPMotion est divisé en trois étapes distinctes.
    Upload et récupération d’informations de la vidéo source
    Dans un premier temps, il est nécessaire de créer un article SPIP et de lui joindre le document vidéo "source".
    Au moment où ce document est joint à l’article, deux actions supplémentaires au comportement normal sont exécutées : La récupération des informations techniques des flux audio et video du fichier ; La génération d’une vignette : extraction d’une (...)

Sur d’autres sites (8116)

  • SDL2 won't play with more than 6 audio channels

    13 juin 2020, par Hiko Haieto

    I am trying to stream (raw) video and audio from a capture device as part of my home media setup (with my pc acting similarly to a receiver in a typical home theatre setup), but the biggest problem I haven't been able to get past is that I haven't been able to get ffplay (using SDL2 as its audio backend) to work with all 8 channels in 7.1 streams - two simply get dropped, despite it recognising 8 channel input or me specifying a 7.1 layout.

    



    I have been able to confirm that all 8 channels are present in the source by first using ffmpeg to save the output of a speaker test to a file and playing that back with both mplayer (which works) and ffplay (which doesn't). I also wrote some minimal code to play the audio directly through SDL's API with the same result, so it's not the fault of ffplay. I might simply use mplayer if it weren't for the fact that piping output from ffmpeg adds too much latency for real-time use. I am using libSDL version 2.0.12 and ffplay 4.2.3, both of which are the latest at the time of writing and are ostensibly supposed to support 7.1 audio.

    



    Using output recorded from speaker-test -c 8, I am using the following to play it back in mplayer :

    



    mplayer -channels 8 -rawaudio channels=8 -format s16le -demuxer rawaudio speaker-test.pcm


    



    and the following to play it back in ffplay :

    



    ffplay -f s16le -ac 8 -af 'channelmap=channel_layout=7.1' speaker-test.pcm


    



    No matter what I try, the two side channels get dropped. I couldn't figure out how to play raw pcm in SDL, so I repeated the same tests with wav output and used the following code to play it back :

    



    #include <sdl2></sdl2>SDL.h>&#xA;&#xA;int main(int argc, char **argv) {&#xA;    SDL_Init(SDL_INIT_AUDIO);&#xA;    SDL_AudioSpec wavSpec;&#xA;    Uint32 wavLength;&#xA;    Uint8 *wavBuffer;&#xA;    SDL_LoadWAV("speaker-test.wav", &amp;wavSpec, &amp;wavBuffer, &amp;wavLength);&#xA;    SDL_AudioDeviceID deviceID = SDL_OpenAudioDevice(NULL, 0, &amp;wavSpec, NULL, 0);&#xA;    SDL_QueueAudio(deviceID, wavBuffer, wavLength);&#xA;    SDL_PauseAudioDevice(deviceID, 0);&#xA;    SDL_Delay(30000);&#xA;    SDL_CloseAudioDevice(deviceID);&#xA;    SDL_FreeWAV(wavBuffer);&#xA;    SDL_Quit();&#xA;    return 0;&#xA;}&#xA;

    &#xA;&#xA;

    The above code exhibits the same behaviour of dropping the two additional side channels, despite it being the latest version of SDL that should have supported 7.1 for many releases now. Why might this be happening, and how might I fix it ?

    &#xA;

  • ClassX installation "codec not found" due to dependencies [migrated]

    25 mars 2014, par khateeb

    ClassX is an interactive lecture streaming system developed in the Electrical Engineering Department at Stanford University.
    Unlike conventional lecture capturing systems, ClassX requires very simple consumer-grade equipment and minimal human operation.

    I faced problems during installing it, I hope you have a solution.

    BTW : I successfully installed it 2 years ago, but now I think the problem as the dependencies and Ubuntu versions are different than the versions we used two years ago.

    Detailed description of the problem :

    • I'm using Ubuntu 12.04
    • I followed the instructions @ ClassX installation guide, and all steps till step 4 are successfully done (the encoder bin file generated).
    • When trying to encode the video using the classX web system, it shows the encoding completed after few seconds.However, there are no tiles generated.
    • I tried to execute the command at CX_log.txt, and the following error appears.

      mahmoud@Mahmoud-HP-Pavilion-dv5-Notebook-PC : $ sudo perl /var/www/ClassXWebSystem/system/publishers/web/actions/encode.pl "/var/www/ClassXWebSystem/content/encoding/FALL_2013_2014/CS106A_FALL_2013_2014/lecSEven" "/var/www/ClassXWebSystem/content/encoding/FALL_2013_2014/CS106A_FALL_2013_2014/.encoding_1372706251" "/var/www/ClassXWebSystem/content/streaming/FALL_2013_2014/CS106A_FALL_2013_2014/lecSEven" "/var/www/ClassXWebSystem/system/publishers/bin" classx y n n
      [sudo] password for mahmoud :
      00068.jpg
      ..
      .
      00068.mp4
      Input #0, mov,mp4,m4a,3gp,3g2,mj2, from '/var/www/ClassXWebSystem/content/encoding/FALL_2013_2014/CS106A_FALL_2013_2014/.encoding_1372706251/00068.mp4' :
      Metadata :
      major_brand : isom
      minor_version : 512
      compatible_brands : isomiso2avc1mp41
      encoder : Lavf52.39.0
      Duration : 00:02:30.05, start : 0.000000, bitrate : 8141 kb/s
      Stream #0.0(und) : Video : h264, yuv420p, 1920x1080 [PAR 1:1 DAR 16:9], 8007 kb/s, 29.95 fps, 29.97 tbr, 2997 tbn, 59.94 tbc
      Stream #0.1(und) : Audio : aac, 44100 Hz, stereo, s16, 128 kb/s
      Output #0, mp4, to '/var/www/ClassXWebSystem/content/encoding/FALL_2013_2014/CS106A_FALL_2013_2014/.encoding_1372706251/stream0.mp4' :
      Stream #0.0 : Video : [0][0][0][0] / 0x0000, yuv420p, 640x360, q=32-36, 64 kb/s, 90k tbn, 14.99 tbc
      codec not found

  • ClassX installation "codec not found" due to dependencies [migrated]

    25 mars 2014, par khateeb

    ClassX is an interactive lecture streaming system developed in the Electrical Engineering Department at Stanford University.
    Unlike conventional lecture capturing systems, ClassX requires very simple consumer-grade equipment and minimal human operation.

    I faced problems during installing it, I hope you have a solution.

    BTW : I successfully installed it 2 years ago, but now I think the problem as the dependencies and Ubuntu versions are different than the versions we used two years ago.

    Detailed description of the problem :

    • I’m using Ubuntu 12.04
    • I followed the instructions @ ClassX installation guide, and all steps till step 4 are successfully done (the encoder bin file generated).
    • When trying to encode the video using the classX web system, it shows the encoding completed after few seconds.However, there are no tiles generated.
    • I tried to execute the command at CX_log.txt, and the following error appears.

      mahmoud@Mahmoud-HP-Pavilion-dv5-Notebook-PC : $ sudo perl /var/www/ClassXWebSystem/system/publishers/web/actions/encode.pl "/var/www/ClassXWebSystem/content/encoding/FALL_2013_2014/CS106A_FALL_2013_2014/lecSEven" "/var/www/ClassXWebSystem/content/encoding/FALL_2013_2014/CS106A_FALL_2013_2014/.encoding_1372706251" "/var/www/ClassXWebSystem/content/streaming/FALL_2013_2014/CS106A_FALL_2013_2014/lecSEven" "/var/www/ClassXWebSystem/system/publishers/bin" classx y n n
      [sudo] password for mahmoud :
      00068.jpg
      ..
      .
      00068.mp4
      Input #0, mov,mp4,m4a,3gp,3g2,mj2, from ’/var/www/ClassXWebSystem/content/encoding/FALL_2013_2014/CS106A_FALL_2013_2014/.encoding_1372706251/00068.mp4’ :
      Metadata :
      major_brand : isom
      minor_version : 512
      compatible_brands : isomiso2avc1mp41
      encoder : Lavf52.39.0
      Duration : 00:02:30.05, start : 0.000000, bitrate : 8141 kb/s
      Stream #0.0(und) : Video : h264, yuv420p, 1920x1080 [PAR 1:1 DAR 16:9], 8007 kb/s, 29.95 fps, 29.97 tbr, 2997 tbn, 59.94 tbc
      Stream #0.1(und) : Audio : aac, 44100 Hz, stereo, s16, 128 kb/s
      Output #0, mp4, to ’/var/www/ClassXWebSystem/content/encoding/FALL_2013_2014/CS106A_FALL_2013_2014/.encoding_1372706251/stream0.mp4’ :
      Stream #0.0 : Video : [0][0][0][0] / 0x0000, yuv420p, 640x360, q=32-36, 64 kb/s, 90k tbn, 14.99 tbc
      codec not found