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  • Supporting all media types

    13 avril 2011, par

    Unlike most software and media-sharing platforms, MediaSPIP aims to manage as many different media types as possible. The following are just a few examples from an ever-expanding list of supported formats : images : png, gif, jpg, bmp and more audio : MP3, Ogg, Wav and more video : AVI, MP4, OGV, mpg, mov, wmv and more text, code and other data : OpenOffice, Microsoft Office (Word, PowerPoint, Excel), web (html, CSS), LaTeX, Google Earth and (...)

  • ANNEXE : Les plugins utilisés spécifiquement pour la ferme

    5 mars 2010, par

    Le site central/maître de la ferme a besoin d’utiliser plusieurs plugins supplémentaires vis à vis des canaux pour son bon fonctionnement. le plugin Gestion de la mutualisation ; le plugin inscription3 pour gérer les inscriptions et les demandes de création d’instance de mutualisation dès l’inscription des utilisateurs ; le plugin verifier qui fournit une API de vérification des champs (utilisé par inscription3) ; le plugin champs extras v2 nécessité par inscription3 (...)

  • Encoding and processing into web-friendly formats

    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).
    Where possible, text is analyzed in order to retrieve the data needed for search engine detection, and then exported as a series of image files.
    All uploaded files are stored online in their original format, so you can (...)

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  • C++ ffmpeg and SDL2 video rendering memory leak

    10 avril 2017, par kj192

    I have made a small program what plays a video in SDL2.0 and FFmpeg.
    The software does work and do it is purpose.
    I have left the software running and I have faced a huge memory consumption and started to look online what can I do against it.
    I have used the following tutorials :
    http://www.developersite.org/906-59411-FFMPEG
    http://ardrone-ailab-u-tokyo.blogspot.co.uk/2012/07/212-ardrone-20-video-decording-ffmpeg.html

    I wonder if someone can give advice what do I do wrong. I have tried valgrind but I can’t find any information. I have did try to comment out sections and what I have seen even if I’m not rendering to the display the memory usage is growing and after delete something still not been freed up :

    if (av_read_frame(pFormatCtx, &packet) >= 0)

    the whole source code is here :
    main :

    #include
    #include <ios>
    #include <iostream>
    #include <fstream>
    #include
    #include <sdl2></sdl2>SDL.h>
    #include "video.h"
    using namespace std;

    void memory()
    {
    using std::ios_base;
    using std::ifstream;
    using std::string;

    double vm_usage     = 0.0;
    double resident_set = 0.0;

    // 'file' stat seems to give the most reliable results
    //
    ifstream stat_stream("/proc/self/stat",ios_base::in);

    // dummy vars for leading entries in stat that we don't care about
    //
    string pid, comm, state, ppid, pgrp, session, tty_nr;
    string tpgid, flags, minflt, cminflt, majflt, cmajflt;
    string utime, stime, cutime, cstime, priority, nice;
    string O, itrealvalue, starttime;

    // the two fields we want
    //
    unsigned long vsize;
    long rss;

    stat_stream >> pid >> comm >> state >> ppid >> pgrp >> session >> tty_nr
               >> tpgid >> flags >> minflt >> cminflt >> majflt >> cmajflt
               >> utime >> stime >> cutime >> cstime >> priority >> nice
               >> O >> itrealvalue >> starttime >> vsize >> rss; // don't care about the rest

    stat_stream.close();

    long page_size_kb = sysconf(_SC_PAGE_SIZE) / 1024; // in case x86-64 is configured to use 2MB pages
    vm_usage     = vsize / 1024.0;
    resident_set = rss * page_size_kb;
    std::cout&lt;&lt;"VM: " &lt;&lt; vm_usage &lt;&lt; " RE:"&lt;&lt; resident_set &lt;&lt; std::endl;
    }


    int main()
    {
    //This example using 1280x800 video
    av_register_all();
    if( SDL_Init(SDL_INIT_VIDEO | SDL_INIT_AUDIO | SDL_INIT_TIMER ))
    {
       fprintf(stderr, "Could not initialize SDL - %s\n", SDL_GetError());
       exit(1);
    }
    SDL_Window* sdlWindow = SDL_CreateWindow("Video Window", SDL_WINDOWPOS_UNDEFINED, SDL_WINDOWPOS_UNDEFINED, 1280, 800, SDL_WINDOW_OPENGL);
    if( !sdlWindow )
    {
       fprintf(stderr, "SDL: could not set video mode - exiting\n");
       exit(1);
    }
    SDL_Renderer* sdlRenderer = SDL_CreateRenderer(sdlWindow, -1, SDL_RENDERER_ACCELERATED | SDL_RENDERER_PRESENTVSYNC | SDL_RENDERER_TARGETTEXTURE);
    SDL_Texture* sdlTexture = SDL_CreateTexture(sdlRenderer, SDL_PIXELFORMAT_YV12, SDL_TEXTUREACCESS_STREAMING, 1280, 800);
    if(!sdlTexture)
    {
       return -1;
    }
    SDL_SetTextureBlendMode(sdlTexture,SDL_BLENDMODE_BLEND );
    //VIDEO RESOLUTION
    SDL_Rect sdlRect;
    sdlRect.x = 0;
    sdlRect.y = 0;
    sdlRect.w = 1280;
    sdlRect.h = 800;    
    memory();
    for(int i = 1; i &lt; 6; i++)
    {
       memory();  
       video* vid = new video("vid.mp4");  
       while (!vid -> getFinished())
       {
           memory();
           vid -> Update(sdlTexture);
           SDL_RenderCopy(sdlRenderer,sdlTexture,&amp;sdlRect,&amp;sdlRect);
           SDL_RenderPresent(sdlRenderer);
       }
       delete vid;
       memory();
    }  
    SDL_DestroyTexture(sdlTexture);
    SDL_DestroyRenderer(sdlRenderer);
    SDL_DestroyWindow(sdlWindow);
    SDL_Quit();
    return 0;
    }
    </fstream></iostream></ios>

    video.cpp

    #include "video.h"

    video::video(const std::string&amp; name) : _finished(false)
    {
    av_register_all();
    pFormatCtx = NULL;
    pCodecCtxOrig = NULL;
    pCodecCtx = NULL;
    pCodec = NULL;
    pFrame = NULL;
    sws_ctx = NULL;
    if (avformat_open_input(&amp;pFormatCtx, name.c_str(), NULL, NULL) != 0)
    {
    _finished = true; // Couldn't open file
    }
    // Retrieve stream information
    if (avformat_find_stream_info(pFormatCtx, NULL) &lt; 0)
    {
    _finished = true; // Couldn't find stream information
    }
    videoStream = -1;
    for (i = 0; i &lt; pFormatCtx->nb_streams; i++)
    {
       if (pFormatCtx->streams[i]->codec->codec_type == AVMEDIA_TYPE_VIDEO)
       {
           videoStream = i;
           break;
       }
    }
    if (videoStream == -1)
    {
       _finished = true; // Didn't find a video stream
    }
    // Get a pointer to the codec context for the video stream
    pCodecCtxOrig = pFormatCtx->streams[videoStream]->codec;
    // Find the decoder for the video stream
    pCodec = avcodec_find_decoder(pCodecCtxOrig->codec_id);
    if (pCodec == NULL)
    {
       fprintf(stderr, "Unsupported codec!\n");
       _finished = true; // Codec not found
    }
    pCodecCtx = avcodec_alloc_context3(pCodec);
    if (avcodec_copy_context(pCodecCtx, pCodecCtxOrig) != 0)
    {
       fprintf(stderr, "Couldn't copy codec context");
       _finished = true; // Error copying codec context
    }
    // Open codec
    if (avcodec_open2(pCodecCtx, pCodec, NULL) &lt; 0)
    {
       _finished = true; // Could not open codec
    }
    // Allocate video frame
    pFrame = av_frame_alloc();
    sws_ctx = sws_getContext(pCodecCtx->width, pCodecCtx->height,
    pCodecCtx->pix_fmt, pCodecCtx->width, pCodecCtx->height,
    AV_PIX_FMT_YUV420P,
    SWS_BILINEAR,
    NULL,
    NULL,
    NULL);
    yPlaneSz = pCodecCtx->width * pCodecCtx->height;
    uvPlaneSz = pCodecCtx->width * pCodecCtx->height / 4;
    yPlane = (Uint8*)malloc(yPlaneSz);
    uPlane = (Uint8*)malloc(uvPlaneSz);
    vPlane = (Uint8*)malloc(uvPlaneSz);
    if (!yPlane || !uPlane || !vPlane)
    {
       fprintf(stderr, "Could not allocate pixel buffers - exiting\n");
       exit(1);
    }
    uvPitch = pCodecCtx->width / 2;
    }
    void video::Update(SDL_Texture* texture)
    {
    if (av_read_frame(pFormatCtx, &amp;packet) >= 0)
    {
       // Is this a packet from the video stream?
       if (packet.stream_index == videoStream)
       {
           avcodec_decode_video2(pCodecCtx, pFrame, &amp;frameFinished, &amp;packet);
           // Did we get a video frame?
           if (frameFinished)
           {
               AVPicture pict;
               pict.data[0] = yPlane;
               pict.data[1] = uPlane;
               pict.data[2] = vPlane;
               pict.linesize[0] = pCodecCtx->width;
               pict.linesize[1] = uvPitch;
               pict.linesize[2] = uvPitch;
               // Convert the image into YUV format that SDL uses
               sws_scale(sws_ctx, (uint8_t const * const *) pFrame->data,pFrame->linesize, 0, pCodecCtx->height, pict.data,pict.linesize);
               SDL_UpdateYUVTexture(texture,NULL,yPlane,pCodecCtx->width,uPlane,uvPitch,vPlane,uvPitch);
           }
       }
       // Free the packet that was allocated by av_read_frame
       av_packet_unref(&amp;packet);
       av_freep(&amp;packet);
    }
    else
    {
       av_packet_unref(&amp;packet);
       av_freep(&amp;packet);
       _finished = true;
    }
    }
    bool video::getFinished()
    {
    return _finished;
    }
    video::~video()
    {
    av_packet_unref(&amp;packet);
    av_freep(&amp;packet);
    av_frame_free(&amp;pFrame);
    av_freep(&amp;pFrame);
    free(yPlane);
    free(uPlane);
    free(vPlane);
    // Close the codec
    avcodec_close(pCodecCtx);
    avcodec_close(pCodecCtxOrig);
    sws_freeContext(sws_ctx);
    // Close the video file
    for (int i = 0; i &lt; pFormatCtx->nb_streams; i++)
    {
       AVStream *stream = pFormatCtx->streams[i];
       avcodec_close(stream->codec);
    }
    avformat_close_input(&amp;pFormatCtx);
    /*av_dict_free(&amp;optionsDict);  
    sws_freeContext(sws_ctx);
    av_free_packet(&amp;packet);
    av_free(pFrameYUV);
    av_free(buffer);
    avcodec_close(pCodecCtx);
    avformat_close_input(&amp;pFormatCtx);*/
    }

    video.h

    #include <string>
    #include <sdl2></sdl2>SDL.h>
    #ifdef __cplusplus
    extern "C" {
    #endif
    #include <libavcodec></libavcodec>avcodec.h>
    #include <libavformat></libavformat>avformat.h>
    #include <libswscale></libswscale>swscale.h>
    #ifdef __cplusplus
    }
    #endif

    class video
    {
      private:
       bool _finished;
       AVFormatContext *pFormatCtx;
       int videoStream;
       unsigned i;
       AVCodecContext *pCodecCtxOrig;
       AVCodecContext *pCodecCtx;
       AVCodec *pCodec;
       AVFrame *pFrame;
       AVPacket packet;
       int frameFinished;
       struct SwsContext *sws_ctx;
       Uint8 *yPlane, *uPlane, *vPlane;
       size_t yPlaneSz, uvPlaneSz;
       int uvPitch;
      public:
       video(const std::string&amp; name);
       ~video();
       void Update(SDL_Texture* texture);
       bool getFinished();
    };
    </string>

    I’m looking forward to your answers

  • Error "Broken file, keyframe not correctly marked" [on hold]

    11 avril 2017, par Александр Патейчук

    When I open a certain .ogv file, I get an error in the dump

    [ogg @ 00f0c400] Broken file, keyframe not correctly marked.

    And I can not play the audio track (the video plays normally), although the VLC media player reproduces this format normally.

    Is it possible to fix "keyframe not correctly marked" ? Other formats with the same code are played back normally.

  • Video made from images using ffmpeg is not seekable in some players

    14 avril 2017, par Satya

    I’m trying to make video from images, used the following command

    ffmpeg -framerate 1/5 -i img%03d.png -c:v libx264 -vf fps=25 -pix_fmt yuv420p out.mp4

    as explained in the link https://trac.ffmpeg.org/wiki/Slideshow. But the problem is in some popular players if I try to seek the video, it plays from the beginning(video restarts from 0:00). How can I make a seeklable video ?