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  • Websites made ​​with MediaSPIP

    2 mai 2011, par

    This page lists some websites based on MediaSPIP.

  • MediaSPIP Core : La Configuration

    9 novembre 2010, par

    MediaSPIP Core fournit par défaut trois pages différentes de configuration (ces pages utilisent le plugin de configuration CFG pour fonctionner) : une page spécifique à la configuration générale du squelettes ; une page spécifique à la configuration de la page d’accueil du site ; une page spécifique à la configuration des secteurs ;
    Il fournit également une page supplémentaire qui n’apparait que lorsque certains plugins sont activés permettant de contrôler l’affichage et les fonctionnalités spécifiques (...)

  • 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.

Sur d’autres sites (7034)

  • How can I mux a MKV and MKA file and get it to play in a browser ?

    28 juin 2017, par Robert

    I’m using ffmpeg to merge .mkv and .mka files into .mp4 files. My current command looks like this :

    ffmpeg -i video.mkv -i audio.mka output_path.mp4

    The audio and video files are pre-signed urls from Amazon S3. Even on a server with sufficient resources, this process is going very slowly. I’ve researched situations where you can tell ffmpeg to skip re-encoding each frame, but I think that in my situation it actually does need to re-encode each frame.

    I’ve downloaded 2 sample files to my macbook pro and have installed ffmpeg locally via homebrew. When I run the command

    ffmpeg -i video.mkv -i audio.mka -c copy output.mp4

    I get the following output :

    ffmpeg version 3.3.2 Copyright (c) 2000-2017 the FFmpeg developers
    
  built with Apple LLVM version 8.1.0 (clang-802.0.42)
    
  configuration: --prefix=/usr/local/Cellar/ffmpeg/3.3.2 --enable-shared --enable-pthreads --enable-gpl --enable-version3 --enable-hardcoded-tables --enable-avresample --cc=clang --host-cflags= --host-ldflags= --enable-libmp3lame --enable-libx264 --enable-libxvid --enable-opencl --disable-lzma --enable-vda
    
  libavutil      55. 58.100 / 55. 58.100
    
  libavcodec     57. 89.100 / 57. 89.100
    
  libavformat    57. 71.100 / 57. 71.100
    
  libavdevice    57.  6.100 / 57.  6.100
    
  libavfilter     6. 82.100 /  6. 82.100
    
  libavresample   3.  5.  0 /  3.  5.  0
    
  libswscale      4.  6.100 /  4.  6.100
    
  libswresample   2.  7.100 /  2.  7.100
    
  libpostproc    54.  5.100 / 54.  5.100
    
Input #0, matroska,webm, from '319_audio_1498590673766.mka':
    
  Metadata:
    
    encoder         : GStreamer matroskamux version 1.8.1.1
    
    creation_time   : 2017-06-27T19:10:58.000000Z
    
  Duration: 00:00:03.53, start: 2.831000, bitrate: 50 kb/s
    
    Stream #0:0(eng): Audio: opus, 48000 Hz, stereo, fltp (default)
    
    Metadata:
    
      title           : Audio
    
Input #1, matroska,webm, from '319_video_1498590673766.mkv':
    
  Metadata:
    
    encoder         : GStreamer matroskamux version 1.8.1.1
    
    creation_time   : 2017-06-27T19:10:58.000000Z
    
  Duration: 00:00:03.97, start: 2.851000, bitrate: 224 kb/s
    
    Stream #1:0(eng): Video: vp8, yuv420p(progressive), 640x480, SAR 1:1 DAR 4:3, 30 tbr, 1k tbn, 1k tbc (default)
    
    Metadata:
    
      title           : Video
    
[mp4 @ 0x7fa4f0806800] Could not find tag for codec vp8 in stream #0, codec not currently supported in container
    
Could not write header for output file #0 (incorrect codec parameters ?): Invalid argument
    
Stream mapping:
    
  Stream #1:0 -> #0:0 (copy)
    
  Stream #0:0 -> #0:1 (copy)
    
    Last message repeated 1 times

    So it appears that the specific encodings I’m working with are vp8 videos and opus audio files, which I believe are incompatible with the .mp4 output container. I would appreciate answers that cover ways of optimally merging vp8 and opus into .mp4 output or answers that point me in the direction of output media formats that are both compatible with vp8 & opus and are playable on web and mobile devices so that I can bypass the re-encoding step altogether.

    EDIT :

    Just wanted to provide a benchmark after following LordNeckbeard’s advice :

    4 min 41 second video transcoded locally on my mac
    

    
LordNeckbeard’s approach : 15 mins 55 seconds (955 seconds)
    
Current approach : 18 mins 49 seconds (1129 seconds)
    

    
18% speed increase

  • lavu : add new D3D11 pixfmt and hwcontext

    6 juin 2017, par wm4
    lavu : add new D3D11 pixfmt and hwcontext

    To be used with the new d3d11 hwaccel decode API.
    

    With the new hwaccel API, we don't want surfaces to depend on the
    
decoder (other than the required dimension and format). The old D3D11VA
    
pixfmt uses ID3D11VideoDecoderOutputView pointers, which include the
    
decoder configuration, and thus is incompatible with the new hwaccel
    
API. This patch introduces AV_PIX_FMT_D3D11, which uses ID3D11Texture2D
    
and an index. It's simpler and compatible with the new hwaccel API.
    

    The introduced hwcontext supports only the new pixfmt.
    

    Frame upload code untested.
    

    Significantly based on work by Steve Lhomme <robux4@gmail.com>, but with
    
heavy changes/rewrites.
    

    Merges Libav commit fff90422d181744cd75dbf011687ee7095f02875.
    

    Signed-off-by : Diego Biurrun <diego@biurrun.de>
    • [DH] doc/APIchanges
    • [DH] libavutil/Makefile
    • [DH] libavutil/hwcontext.c
    • [DH] libavutil/hwcontext.h
    • [DH] libavutil/hwcontext_d3d11va.c
    • [DH] libavutil/hwcontext_d3d11va.h
    • [DH] libavutil/hwcontext_internal.h
    • [DH] libavutil/pixdesc.c
    • [DH] libavutil/pixfmt.h
    • [DH] libavutil/version.h

  • ffmpeg : how to replace img_convert() with sws_scale()

    23 juillet 2017, par Yoohoo

    I have an old version FFmpeg code like this ：

    int ret = img_convert((AVPicture *)picture, c->pix_fmt,
    
                      (AVPicture *)input_picture, (PixelFormat)input_pix_fmt,
    
                      width, height);
    
if (ret &lt; 0)
    
        return false;

    I noticed that in new ffmpeg, the img_convert() has been replaced by sws_scale(), I followed the format and change like this :

    int w = width;
    
int h = height;
    

    
static struct SwsContext *img_convert_ctx 
    
                = sws_getContext(w, h, (PixelFormat)input_pix_fmt, 
    
                                 w, h, c->pix_fmt, 
    
                                 SWS_BICUBIC, NULL, NULL, NULL);
    

    
int ret = sws_scale(img_convert_ctx,
    
                    input_picture->data, 
    
                    input_picture->linesize,
    
                    0,
    
                    height, 
    
                    (AVPicture *)picture, 
    
                    (AVPicture *)picture);
    

    
if (ret &lt; 0) {
    
   return false;
    
}
    

    
sws_freeContext(img_convert_ctx);

    but it gives the error :

    error: cannot convert ‘AVPicture*’ to ⏎
    
       ‘uint8_t* const* {aka unsigned char* const*}’ for argument ‘6’ to ⏎
    
       ‘int sws_scale(SwsContext*, const uint8_t* const*, ⏎
    
       const int*, int, int, uint8_t* const*, const int*)’

    It seems the error falls in the last two parameters of sws_scale. How should I modify it ?

    And is it caused by c and c++ incompatible problem ? I am now run FFmpeg in C, and use extern C to include the headers.

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