Recherche avancée

Médias (0)

Mot : - Tags -/auteurs

Aucun média correspondant à vos critères n’est disponible sur le site.

Autres articles (25)

  • Le plugin : Gestion de la mutualisation

    2 mars 2010, par

    Le plugin de Gestion de mutualisation permet de gérer les différents canaux de mediaspip depuis un site maître. Il a pour but de fournir une solution pure SPIP afin de remplacer cette ancienne solution.
    Installation basique
    On installe les fichiers de SPIP sur le serveur.
    On ajoute ensuite le plugin "mutualisation" à la racine du site comme décrit ici.
    On customise le fichier mes_options.php central comme on le souhaite. Voilà pour l’exemple celui de la plateforme mediaspip.net :
    < ?php (...)

Sur d’autres sites (1459)

  • FFmpeg concat and then add soundtrack results in a soundtrack that stutters

    25 mars 2016, par JennHarper

    I am trying to create a video composed of clips of images and videos. For the clips of images, I use ffmpeg to create a video file and then I add a silent audio stream through these two steps :

    ffmpeg.exe -loop 1 -i MyImage.png -codec:v libx264 -t 4.0 -profile:v high -preset slow -r 25 -b:v 500k -maxrate 500k -pix_fmt yuv420p -vf scale=1280:720 MyImageMovie.mp4
    

    
ffmpeg.exe -f lavfi -i anullsrc=r=48000 -i MyImageMovie.mp4 -shortest -c:v copy -c:a aac -strict experimental -y MyImageMovieWithSilentAudioStream.mp4

    Then I combine my video clips and image clips with

    ffmpeg.exe -f concat -i videoList.txt -c copy -y concatVideo.mp4

    At this point, the video looks good, any video clips that have audio streams seemed well synced to the video.

    Now I add a soundtrack :

    ffmpeg.exe -i concatVideo.mp4 -i soundtrack.mp3 -ar 48000 -filter_complex "[1:a]apad [b] ; [0:a][b]amerge=inputs=2[a]" -map 0:v -map "[a]" -c:v copy -ac 2 -shortest -y FinalVideo.mp4

    The problem is that the soundtrack on FinalVideo.mp4 stutters at some (not all) of the concatenation joints.

    I suspect it has to do with the audio stream and the video stream of the Image clips not being perfectly aligned. The aac has .0231s resolution and the video has 0.04s resolution. When I ffprobe the MyImageMovieWithSilentAudioStream.mp4 the duration is 4.00s but the start is 0.0213.

    If my concatenated video has several of these image clips, the error can start to accumulate.

    What can I do to keep the video and audio in sync and add a soundtrack that doesn’t stutter ?

    Also, this is a little interesting, I don’t hear the stutter when the final video is played on Windows Media Player, but it is there if I play it on VLC or via the html native video element.

  • Expose the state of the jqXHR object as state() method on the data argument.

    18 mars 2013, par blueimp

    m js/jquery.fileupload.js Expose the state of the jqXHR object as state() method on the data argument.

  • png : split header state and data state in two separate variables.

    3 avril 2017, par Ronald S. Bultje
    png : split header state and data state in two separate variables.

    Fixes a reported (but false) race condition in tsan for fate-apng :
    

    WARNING : ThreadSanitizer : data race (pid=6274)
    
  Read of size 4 at 0x7d680001ec78 by main thread (mutexes : write M1338) :
    
    #0 update_thread_context src/libavcodec/pngdec.c:1456 (ffmpeg+0x000000dacf0c)
    
[..]
    
  Previous write of size 4 at 0x7d680001ec78 by thread T1 (mutexes : write M1335) :
    
    #0 decode_idat_chunk src/libavcodec/pngdec.c:737 (ffmpeg+0x000000dae951)
    • [DH] libavcodec/png.h
    • [DH] libavcodec/pngdec.c

Navigation