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    Puis-je poster des contenus à partir d’une tablette Ipad ?
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    13 avril 2011, par

    MediaSPIP automatically converts uploaded files to internet-compatible formats.
    Video files are encoded in MP4, Ogv and WebM (supported by HTML5) and MP4 (supported by Flash).
    Audio files are encoded in MP3 and Ogg (supported by HTML5) and MP3 (supported by Flash).
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    13 juin 2013, par

    Un masque de formulaire consiste en la personnalisation du formulaire de mise en ligne des médias, rubriques, actualités, éditoriaux et liens vers des sites.
    Chaque formulaire de publication d’objet peut donc être personnalisé.
    Pour accéder à la personnalisation des champs de formulaires, il est nécessaire d’aller dans l’administration de votre MediaSPIP puis de sélectionner "Configuration des masques de formulaires".
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Sur d’autres sites (7075)

  • Theatrical quality ffmpeg/x264 encoding of a high-motion 1080p video

    2 décembre 2011, par Ian

    I've been struggling with encoding videos using FFMPEG and x264. The output stutters when played back in Quicktime, while in VLC it shows a lot of compression artifacts at the same places Quicktime stutters. So it seems like Quicktime is stuttering because it's trying to suppress the corruption/artifacts.

    The videos have a lot of random motion in them, including frames where 75% of the pixels will change at a random interval (the video is software generated so it's truly pseudo-random). The compression seems to be choking in these places where it's likely detecting a "scene cut" incorrectly. It also seems to choke at regular intervals where I guess it's doing a keyframe.

    I've based my encoding preset off of the x264-hq preset that comes with FFMPEG. I've tried turning off scene cut detection, and playing with the keyint/g and keyint_min options. Setting g to 1 makes it work, but blows out the filesize. I've tried the lossless presets, but they won't playback at all in Quicktime. Oddly, I haven't had any problems when working with a lower-resolution test video (1440x810).

    Here's the preset I have right now, which works, but yields a file that's approximately 60% larger than the (non-working) hq preset yields. Is there any way to improve upon this ? The filesize doesn't matter much, I just want something that will playback anywhere and be very high quality.

    coder=1
    flags=+loop
    cmp=+chroma
    partitions=+parti8x8+parti4x4+partp8x8+partp4x4+partb8x8
    me_method=umh
    subq=8
    me_range=16
    g=1
    keyint_min=1
    sc_threshold=0
    i_qfactor=0.71
    b_strategy=1crf=20
    qcomp=0.6
    qmin=20
    qmax=51
    qdiff=4
    bf=16
    refs=4
    trellis=1
    flags2=+dct8x8+wpred+bpyramid+mixed_refs
    wpredp=2
    

    Here's the command :

    ffmpeg \
      -r 60 -i "frame-%06d.tiff" \
      -vcodec libx264 -vpre my_preset \
      -threads 0 \
      -r 60 -an -f out.mp4
    
  • Theatrical quality ffmpeg/x264 encoding of a high-motion 1080p video

    2 décembre 2011, par Ian

    I've been struggling with encoding videos using FFMPEG and x264. The output stutters when played back in Quicktime, while in VLC it shows a lot of compression artifacts at the same places Quicktime stutters. So it seems like Quicktime is stuttering because it's trying to suppress the corruption/artifacts.

    The videos have a lot of random motion in them, including frames where 75% of the pixels will change at a random interval (the video is software generated so it's truly pseudo-random). The compression seems to be choking in these places where it's likely detecting a "scene cut" incorrectly. It also seems to choke at regular intervals where I guess it's doing a keyframe.

    I've based my encoding preset off of the x264-hq preset that comes with FFMPEG. I've tried turning off scene cut detection, and playing with the keyint/g and keyint_min options. Setting g to 1 makes it work, but blows out the filesize. I've tried the lossless presets, but they won't playback at all in Quicktime. Oddly, I haven't had any problems when working with a lower-resolution test video (1440x810).

    Here's the preset I have right now, which works, but yields a file that's approximately 60% larger than the (non-working) hq preset yields. Is there any way to improve upon this ? The filesize doesn't matter much, I just want something that will playback anywhere and be very high quality.

    coder=1
    flags=+loop
    cmp=+chroma
    partitions=+parti8x8+parti4x4+partp8x8+partp4x4+partb8x8
    me_method=umh
    subq=8
    me_range=16
    g=1
    keyint_min=1
    sc_threshold=0
    i_qfactor=0.71
    b_strategy=1crf=20
    qcomp=0.6
    qmin=20
    qmax=51
    qdiff=4
    bf=16
    refs=4
    trellis=1
    flags2=+dct8x8+wpred+bpyramid+mixed_refs
    wpredp=2
    

    Here's the command :

    ffmpeg \
      -r 60 -i "frame-%06d.tiff" \
      -vcodec libx264 -vpre my_preset \
      -threads 0 \
      -r 60 -an -f out.mp4
    
  • watermark video with ffmpeg at specified duration [duplicate]

    5 avril 2013, par Paige Cherry

    This question is an exact duplicate of :

    Is it possible to watermark video with ffmpeg at specified intervals and in the whole video duration ?

    I am using windows.