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  • Gestion générale des documents

    13 mai 2011, par

    MédiaSPIP ne modifie jamais le document original mis en ligne.
    Pour chaque document mis en ligne il effectue deux opérations successives : la création d’une version supplémentaire qui peut être facilement consultée en ligne tout en laissant l’original téléchargeable dans le cas où le document original ne peut être lu dans un navigateur Internet ; la récupération des métadonnées du document original pour illustrer textuellement le fichier ;
    Les tableaux ci-dessous expliquent ce que peut faire MédiaSPIP (...)

  • 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 (...)

Sur d’autres sites (12261)

  • Why iFrame is a good idea

    15 octobre 2009

    I’ve seen some hilariously uninformed posts about the new Apple iFrame specification. Let me take a minute to explain what it actually is.

    First off, as opposed to what the fellow in the Washington Post writes, it’s not really a new format. iFrame is just a way of using formats that we’ve already know and love. As the name suggests, iFrame is just an i-frame only H.264 specification, using AAC audio. An intraframe version of H.264 eh ? Sounds a lot like AVC-Intra, right ? Exactly. And for exactly the same reasons - edit-ability. Whereas AVC-Intra targets the high end, iFrame targets the low end.

    Even when used in intraframe mode, H.264 has some huge advantage over the older intraframe codecs like DV or DVCProHD. For example, significantly better entropy coding, adaptive quantization, and potentially variable bitrates. There are many others. Essentially, it’s what happens when you take DV and spend another 10 years working on making it better. That’s why Panasonic’s AVC-Intra cameras can do DVCProHD quality video at half (or less) the bitrate.

    Why does iFrame matter for editing ? Anyone who’s tried to edit video from one of the modern H.264 cameras without first transcoding to an intraframe format has experienced the huge CPU demands and sluggish performance. Behind the scenes it’s even worse. Because interframe H.264 can have very long GOPs, displaying any single frame can rely on dozens or even hundreds of other frames. Because of the complexity of H.264, building these frames is very high-cost. And it’s a variable cost. Decoding the first frame in a GOP is relatively trivial, while decoding the middle B-frame can be hugely expensive.

    Programs like iMovie mask that from the user in some cases, but at the expensive of high overhead. But, anyone who’s imported AVC-HD video into Final Cut Pro or iMovie knows that there’s a long "importing" step - behind the scenes, the applications are transcoding your video into an intraframe format, like Apple Intermediate or ProRes. It sort of defeats one of the main purposes of a file-based workflow.

    You’ve also probably noticed the amount of time it takes to export a video in an interframe format. Anyone who’s edited HDV in Final Cut Pro has experienced this. With DV, doing an "export to quicktime" is simply a matter of Final Cut Pro rewriting all of the data to disk - it’s essentially a file copy. With HDV, Final Cut Pro has to do a complete reencode of the whole timeline, to fit everything into the new GOP structure. Not only is this time consuming, but it’s essentially a generation loss.

    iFrame solves these issues by giving you an intraframe codec, with modern efficiency, which can be decoded by any of the H.264 decoders that we already know and love.

    Having this as an optional setting on cameras is a huge step forward for folks interested in editing video. Hopefully some of the manufacturers of AVC-HD cameras will adopt this format as well. I’ll gladly trade a little resolution for instant edit-ability.

  • FFMPeg OS X Lion [closed]

    19 février 2013, par Infinite Possibilities

    I've build FFmpeg from source, using this tutorial.

    It is working very well, but I have a problem. I did the compile on OS X 10.8 and when I try to run on OS X 10.7, it fails and the error code says that it isn't built for OS X 10.7.

    Is there any configure parameter that I can specify this ?

  • audio extracted from flv file via ffmpeg is of shorter duration than the actual flv video [closed]

    11 janvier 2013, par user1961143

    I have extracted audio from flv file via ffmpeg using this command :-

    ffmpeg -i 164_29.flv v19.mp3

    The flv videos duration is 3 minutes but the audio is of 2 mins 20 seconds only. On searching i found that the silent pieces of audio are removed when generating audio from ffmpeg. But i need the audio file to be of exactly same duration as flv video as later i need to put this audio in the flv video itself. Please help as this is urgent for our project. I am running the FFMpeg via .net windows service, so in case you know any other tool which can extract the audio of same duration as video and can be run via .net, it would be useful too.

    Console output :

    C :\Users\ritika.thakur>ffmpeg -i 164_29.flv v19.mp3
    ffmpeg version N-47062-g26c531c Copyright (c) 2000-2012 the FFmpeg developers
    built on Nov 25 2012 12:23:20 with gcc 4.7.2 (GCC)
    configuration : —disable-static —enable-shared —enable-gpl —enable-version —disable-pthreads —enable-runtime-cpudetect —enable-avisynth —enable-bzlib —enable-frei0r —enable-libass —enable-libopencore-amrnb —enable-libopencore-amrwb —enable-libfreetype —enable-libgsm —enable-libmp3lame —enable-libnut -enable-libopenjpeg —enable-libopus —enable-librtmp —enable-libschroedinger -enable-libspeex —enable-libtheora —enable-libutvideo —enable-libvo-aacenc —enable-libvo-amrwbenc —enable-libvorbis —enable-libvpx —enable-libx264 —enale-libxavs —enable-libxvid —enable-zlib
    libavutil 52. 9.100 / 52. 9.100
    libavcodec 54. 77.100 / 54. 77.100
    libavformat 54. 37.100 / 54. 37.100
    libavdevice 54. 3.100 / 54. 3.100
    libavfilter 3. 23.102 / 3. 23.102
    libswscale 2. 1.102 / 2. 1.102
    libswresample 0. 17.101 / 0. 17.101
    libpostproc 52. 2.100 / 52. 2.100
    Input #0, flv, from '164_29.flv' :
    Metadata :
    canSeekToEnd : false
    createdby : FMS 4.0
    creationdate : Tue Jan 08 00:26:19 2013
    Duration : 00:03:04.08, start : 0.000000, bitrate : 283
    kb/s
    Stream #0:0 : Video : flv1, yuv420p, 320x240, 1k tbr, 1k tbn, 1k tbc
    Stream #0:1 : Audio : nellymoser, 22050 Hz, mono, flt
    Output #0, mp3, to 'v19.mp3' :
    Metadata :
    canSeekToEnd : false
    createdby : FMS 4.0
    creationdate : Tue Jan 08 00:26:19 2013
    TSSE : Lavf54.37.100
    Stream #0:0 : Audio : mp3, 22050 Hz, mono, fltp
    Stream mapping :
    Stream #0:1 -> #0:0 (nellymoser -> libmp3lame)
    Press [q] to stop, [?] for help
    size= 567kB time=00:03:04.13 bitrate= 25.2kbits/s video:0kB audio:567kB subtitle:0 global headers:0kB muxing overhead 0.051503%

    This is the output of console for both video and audio file separately :-

    Microsoft Windows [Version 6.1.7601]
    Copyright (c) 2009 Microsoft Corporation. All rights reserved.

    C :\Users\ritika.thakur>ffmpeg -i v19.mp3

    ffmpeg version N-47062-g26c531c Copyright (c) 2000-2012 the FFmpeg developers
    built on Nov 25 2012 12:23:20 with gcc 4.7.2 (GCC)
    configuration : —disable-static —enable-shared —enable-gpl —enable-version3
    —disable-pthreads —enable-runtime-cpudetect —enable-avisynth —enable-bzlib
    — enable-frei0r —enable-libass —enable-libopencore-amrnb —enable-libopencore-
    amrwb —enable-libfreetype —enable-libgsm —enable-libmp3lame —enable-libnut -
    - enable-libopenjpeg —enable-libopus —enable-librtmp —enable-libschroedinger -
    - enable-libspeex —enable-libtheora —enable-libutvideo —enable-libvo-aacenc —
    enable-libvo-amrwbenc —enable-libvorbis —enable-libvpx —enable-libx264 —enab
    le-libxavs —enable-libxvid —enable-zlib
    libavutil 52. 9.100 / 52. 9.100
    libavcodec 54. 77.100 / 54. 77.100
    libavformat 54. 37.100 / 54. 37.100
    libavdevice 54. 3.100 / 54. 3.100
    libavfilter 3. 23.102 / 3. 23.102
    libswscale 2. 1.102 / 2. 1.102
    libswresample 0. 17.101 / 0. 17.101
    libpostproc 52. 2.100 / 52. 2.100
    [mp3 @ 0056e780] max_analyze_duration 5000000 reached at 5015510
    Input #0, mp3, from 'v19.mp3' :
    Metadata :
    canSeekToEnd : false
    createdby : FMS 4.0
    creationdate : Tue Jan 08 00:26:19 2013
    encoder : Lavf54.37.100
    Duration : 00:02:25.14, start : 0.000000, bitrate : 32 kb/s
    Stream #0:0 : Audio : mp3, 22050 Hz, mono, s16, 32 kb/s
    At least one output file must be specified

    C :\Users\ritika.thakur>ffmpeg -i 164_29.flv

    ffmpeg version N-47062-g26c531c Copyright (c) 2000-2012 the FFmpeg developers
    built on Nov 25 2012 12:23:20 with gcc 4.7.2 (GCC)
    configuration : —disable-static —enable-shared —enable-gpl —enable-version3
    —disable-pthreads —enable-runtime-cpudetect —enable-avisynth —enable-bzlib
    — enable-frei0r —enable-libass —enable-libopencore-amrnb —enable-libopencore-
    amrwb —enable-libfreetype —enable-libgsm —enable-libmp3lame —enable-libnut -
    - enable-libopenjpeg —enable-libopus —enable-librtmp —enable-libschroedinger -
    - enable-libspeex —enable-libtheora —enable-libutvideo —enable-libvo-aacenc —
    enable-libvo-amrwbenc —enable-libvorbis —enable-libvpx —enable-libx264 —enab
    le-libxavs —enable-libxvid —enable-zlib
    libavutil 52. 9.100 / 52. 9.100
    libavcodec 54. 77.100 / 54. 77.100
    libavformat 54. 37.100 / 54. 37.100
    libavdevice 54. 3.100 / 54. 3.100
    libavfilter 3. 23.102 / 3. 23.102
    libswscale 2. 1.102 / 2. 1.102
    libswresample 0. 17.101 / 0. 17.101
    libpostproc 52. 2.100 / 52. 2.100
    Input #0, flv, from '164_29.flv' :
    Metadata :
    canSeekToEnd : false
    createdby : FMS 4.0
    creationdate : Tue Jan 08 00:26:19 2013
    Duration : 00:03:04.08, start : 0.000000, bitrate : 283 kb/s
    Stream #0:0 : Video : flv1, yuv420p, 320x240, 1k tbr, 1k tbn, 1k tbc
    Stream #0:1 : Audio : nellymoser, 22050 Hz, mono, flt
    At least one output file must be specified

    If you see the duration of video is of 3:04 but audio extracted from it is of 2:25 only.
    Actually i am using ffmpeg overlay to show two videos side by side in our debate project for the client. Now ffmpeg takes audio from first video by default. But we want the audio from both videos together as a debate going on. Hence I thought of a solution to extract audio from both videos and merge them and than apply them to the overlayed video. This will all work perfectly only if I get the complete audio from the video file i.e. of equal duration.
    For more information i am writing here the overlay command we are using :-

     **ffmpeg -i 164_29.flv  -vf "[in] scale=359:320, pad=2*iw+6:ih
    
  [left];    movie=164_30.flv, scale=359:320 [right]; [left][right] 
    
  overlay=365:0  [out]" -b:v 3600k -y a1.flv**
    

    
 **This is the console output of this overlay command:-**

    C :\Users\ritika.thakur>ffmpeg -i 164_29.flv -vf "[in] scale=359:320, pad=2*iw+6
    :ih [left] ; movie=164_30.flv, scale=359:320 [right] ; [left][right] overlay=365:0
    [out]" -b:v 3600k -y a1.flv
    ffmpeg version N-47062-g26c531c Copyright (c) 2000-2012 the FFmpeg developers
    built on Nov 25 2012 12:23:20 with gcc 4.7.2 (GCC)
    configuration : —disable-static —enable-shared —enable-gpl —enable-version3
    —disable- pthreads —enable-runtime-cpudetect —enable- avisynth
    —enable-bzlib —enable
    -frei0r
    —enable-libass —enable-libopencore-amrnb —enable-libopencore-amrwb
    —enable- libfreetype —enable-libgsm —enable-libmp3lame —enable-libnut
    —enable-libopenjpeg —enable-libopus —enable-librtmp —enable-libschroedinger
    — enable-
    libspeex —enable-libtheora —enable- libutvideo
    —enable-libvo-aacenc —
    enable-libvo-amrwbenc —enable-libvorbis —enable-libvpx
    —enable-libx264 —enab
    le-libxavs —enable-libxvid —enable-zlib
    libavutil 52. 9.100 / 52. 9.100
    libavcodec 54. 77.100 / 54. 77.100
    libavformat 54. 37.100 / 54. 37.100
    libavdevice 54. 3.100 / 54. 3.100
    libavfilter 3. 23.102 / 3. 23.102
    libswscale 2. 1.102 / 2. 1.102
    libswresample 0. 17.101 / 0. 17.101
    libpostproc 52. 2.100 / 52. 2.100
    Input #0, flv, from '164_29.flv' :
    Metadata :
    canSeekToEnd : false
    createdby : FMS 4.0
    creationdate : Tue Jan 08 00:26:19 2013
    Duration : 00:03:04.08, start : 0.000000, bitrate : 283 kb/s
    Stream #0:0 : Video : flv1, yuv420p, 320x240, 1k tbr, 1k tbn, 1k tbc
    Stream #0:1 : Audio : nellymoser, 22050 Hz, mono, flt
    Output #0, flv, to 'a1.flv' :
    Metadata :
    canSeekToEnd : false
    createdby : FMS 4.0
    creationdate : Tue Jan 08 00:26:19 2013
    encoder : Lavf54.37.100
    Stream #0:0 : Video : flv1 ([2][0][0][0] / 0x0002), yuv420p, 724x320, q=2-31,
    3600 kb/s, 1k tbn, 1k tbc
    Stream #0:1 : Audio : mp3 ([2][0][0][0] / 0x0002), 22050 Hz, mono, fltp
    Stream mapping :
    Stream #0:0 -> #0:0 (flv -> flv)
    Stream #0:1 -> #0:1 (nellymoser -> libmp3lame)
    Press [q] to stop, [?] for help
    frame= 83 fps=0.0 q=4.1 size= 343kB time=00:00:07.01 bitrate= 401.2kbits/s
    frame= 149 fps=149 q=2.3 size= 861kB time=00:00:14.87 bitrate= 473.9kbits/s
    frame= 223 fps=148 q=2.0 size= 1492kB time=00:00:22.00 bitrate= 555.4kbits/s
    frame= 308 fps=153 q=2.0 size= 2195kB time=00:00:28.64 bitrate= 627.8kbits/s
    frame= 391 fps=156 q=2.0 size= 2858kB time=00:00:34.06 bitrate= 687.4kbits/s
    frame= 478 fps=159 q=2.0 size= 3541kB time=00:00:39.55 bitrate= 733.4kbits/s
    frame= 547 fps=156 q=2.0 size= 4293kB time=00:00:46.80 bitrate= 751.5kbits/s
    frame= 645 fps=161 q=2.0 size= 4896kB time=00:00:51.63 bitrate= 776.8kbits/s
    Buffer queue overflow, dropping.
    [Parsed_overlay_4 @ 0152ca80] Buffer queue overflow, dropping.
    Last message repeated 16 times
    frame= 731 fps=162 q=2.0 size= 5418kB time=00:00:56.61 bitrate= 784.0kbits/s
    Buffer queue overflow, dropping.
    [Parsed_overlay_4 @ 0152ca80] Buffer queue overflow, dropping.
    Last message repeated 49 times
    frame= 794 fps=158 q=2.0 size= 5802kB time=00:01:02.37 bitrate= 762.1kbits/s
    frame= 886 fps=160 q=2.0 size= 6363kB time=00:01:07.00 bitrate= 778.0kbits/s
    Buffer queue overflow, dropping.
    [Parsed_overlay_4 @ 0152ca80] Buffer queue overflow, dropping.
    Last message repeated 29 times
    frame= 954 fps=158 q=2.0 size= 6785kB time=00:01:13.31 bitrate= 758.2kbits/s
    frame= 1056 fps=162 q=2.0 size= 7377kB time=00:01:16.94 bitrate= 785.4kbits/s
    Buffer queue overflow, dropping.
    [Parsed_overlay_4 @ 0152ca80] Buffer queue overflow, dropping.
    Last message repeated 30 times
    frame= 1130 fps=161 q=2.0 size= 7789kB time=00:01:22.19 bitrate= 776.3kbits/s
    frame= 1217 fps=162 q=2.0 size= 8372kB time=00:01:27.68 bitrate= 782.1kbits/s
    frame= 1306 fps=163 q=2.0 size= 9074kB time=00:01:32.86 bitrate= 800.5kbits/s
    frame= 1393 fps=163 q=1.6 size= 9700kB time=00:01:38.41 bitrate= 807.3kbits/s
    frame= 1475 fps=163 q=2.0 size= 10278kB time=00:01:44.03 bitrate= 809.4kbits/s
    frame= 1568 fps=164 q=2.0 size= 10825kB time=00:01:48.52 bitrate= 817.1kbits/s
    frame= 1658 fps=165 q=2.0 size= 11439kB time=00:01:53.44 bitrate= 826.0kbits/s
    frame= 1734 fps=165 q=2.0 size= 12027kB time=00:01:58.31 bitrate= 832.7kbits/s
    frame= 1792 fps=162 q=2.0 size= 12579kB time=00:02:03.41 bitrate= 835.0kbits/s
    frame= 1851 fps=160 q=2.0 size= 13284kB time=00:02:10.74 bitrate= 832.3kbits/s
    frame= 1929 fps=160 q=2.0 size= 13922kB time=00:02:16.85 bitrate= 833.3kbits/s
    frame= 2010 fps=160 q=2.0 size= 14652kB time=00:02:23.39 bitrate= 837.1kbits/s
    frame= 2102 fps=161 q=2.0 size= 15329kB time=00:02:28.86 bitrate= 843.6kbits/s
    frame= 2200 fps=162 q=2.0 size= 15963kB time=00:02:34.08 bitrate= 848.7kbits/s
    frame= 2292 fps=163 q=2.0 size= 16554kB time=00:02:38.96 bitrate= 853.1kbits/s
    frame= 2378 fps=163 q=2.0 size= 17157kB time=00:02:44.50 bitrate= 854.4kbits/s
    frame= 2468 fps=164 q=2.0 size= 17826kB time=00:02:49.50 bitrate= 861.5kbits/s
    frame= 2564 fps=165 q=2.0 size= 18489kB time=00:02:54.43 bitrate= 868.3kbits/s
    Buffer queue overflow, dropping.
    [Parsed_overlay_4 @ 0152ca80] Buffer queue overflow, dropping.
    Last message repeated 15 times
    frame= 2647 fps=165 q=2.0 size= 19079kB time=00:02:59.53 bitrate= 870.6kbits/s
    frame= 2728 fps=165 q=2.0 Lsize= 19703kB time=00:03:04.13 bitrate= 876.6kbits/
    s video:19006kB audio:567kB subtitle:0 global headers:0kB muxing overhead 0.663315%

    Everything is working fine except that we want audio from both videos playing together in final overlayed file. I would be highly grateful if you can help in this and let me know if its possible to do via ffmpeg or not.

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