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  • Publier sur MédiaSpip

    13 juin 2013

    Puis-je poster des contenus à partir d’une tablette Ipad ?
    Oui, si votre Médiaspip installé est à la version 0.2 ou supérieure. Contacter au besoin l’administrateur de votre MédiaSpip pour le savoir

  • Use, discuss, criticize

    13 avril 2011, par

    Talk to people directly involved in MediaSPIP’s development, or to people around you who could use MediaSPIP to share, enhance or develop their creative projects.
    The bigger the community, the more MediaSPIP’s potential will be explored and the faster the software will evolve.
    A discussion list is available for all exchanges between users.

  • 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 (...)

Sur d’autres sites (8939)

  • Revision 6ddf1e152a : Fix int64_t to unsigned int conversion warnings Use unsigned int type to store

    28 août 2014, par Jingning Han

    Changed Paths :
     Modify /vp9/encoder/vp9_rdopt.c



    Fix int64_t to unsigned int conversion warnings

    Use unsigned int type to store the sse in the pixel domain. The
    precision is sufficient to handle sse of block size up to 64x64.
    The transform domain version however needs int64_t, since there is
    a transfer gain applied in the forward transformation that might
    cause unsigned int overflow.

    Change-Id : Ifef97c38597e426262290f35341fbb093cf0a079

  • problem in loading texture from AVFrame(android)

    25 mars 2013, par SieuTruc

    I get a problem when loading data from AVFrame to openGL :

    int target_width = 320;
                   int target_height = 240;
                   img_convert_ctx = sws_getContext(pCodecCtx->width, pCodecCtx->height,
                                              pCodecCtx->pix_fmt,
                                              target_width, target_height, PIX_FMT_RGBA, SWS_FAST_BILINEAR,
                                              NULL, NULL, NULL);
                   if(img_convert_ctx == NULL) {
                       LOGE("could not initialize conversion context\n");
                       return;
                   }
                   sws_scale(img_convert_ctx, (const uint8_t* const*)pFrame->data, pFrame->linesize, 0, pCodecCtx->height, pFrameRGB->data, pFrameRGB->linesize);
                   //free(data);
                   int line=target_width*target_height*4;
                   data=(char*)malloc(line);
                   if (!data)
                       LOGE("create data frame fail");
                   LOGE("successful data");
                   filldata(data,pFrameRGB,target_width,target_height);

    with function filldata as :

       static void filldata(char *data,AVFrame *pFrame,int w,int h)
    {uint8_t *frameLine;
       int  yy;
       int i=0;

    for (yy = 0; yy < h; yy++) {

    frameLine = (uint8_t *)pFrame->data[0] + (yy * pFrame->linesize[0]);

    int xx;

    for (xx = 0; xx < w; xx++) {
               int in_offset = xx * 4;

    data[i++] = frameLine[in_offset];

    data[i++] = frameLine[in_offset+1];

    data[i++] = frameLine[in_offset+2];

    data[i++] = frameLine[in_offset+3];
           }
       }
    }

    After that i use data to transfer to

    glTexImage2D(GL_TEXTURE_2D, 0, GL_RGBA, *wi, *he, 0, GL_RGBA, GL_UNSIGNED_BYTE, (GLvoid*)data);

    but it cannot show texture, maybe data above and data in function gltextimage2D are different.
    Please help me figure out what is the format for gltextimage2D so i can configure data to show texture. OR anyone has some sample code to show me.

  • ffmpeg buffer not released

    11 mars 2013, par ByteByter

    So, I have written a basic decoder for ffmpeg that simply reads the input frames pixel data (Stored using RGB 8 format), and places it directly into the output buffer. (Also RGB 8) The problem is that when I use this decoder in ffmpeg, it says that there is 1 unreleased buffer.(Tested using ffmpeg -i Test.utah Test.png). Unfortunately, I am unsure of what buffer it is talking about, as I am not creating my own buffer. I have tried releasing the AVContext's coded_frame buffer in my decoders closing method, but this causes segmentation faults.

    Any help would be greatly appreciated.

    static int decode_frame(AVCodecContext *avctx, void *data, int *got_frame, AVPacket *avpkt)
    {
       int ret;           /*Hold return from get_buffer */
       int skipSize;      /*Number of dummy bytes to skip per line*/
       int fseek=8;       /*Location of the first pixel*/
       int i=0; int j=0;  /*Output buffer seek index/Input Buffer seek index*/
       const uint8_t *buf = avpkt->data; /*Hold a pointer to the input buffer*/
       AVFrame *pict=data; /*Hold a pointer to the output buffer*/

       /*Set the output pixel format to RGB8*/
       avctx->pix_fmt = AV_PIX_FMT_RGB8;

       /*Get the width and height*/
       bytestream_get_le32(&buf);
       avctx->width=bytestream_get_le16(&buf);
       avctx->height=bytestream_get_le16(&buf);

       /*Release the old buffer*/
       if (pict->data[0]) avctx->release_buffer(avctx, pict);

       /*Aquire a large enough data buffer to hold the decompressed picture*/
       if (ret=ff_get_buffer(avctx, pict) < 0) return ret;
       skipSize=pict->linesize[0] - avctx->width;

       /*Transfer input buffer to output buffer*/
       for(int y=0;yheight;y++){
           for(int x=0;xwidth;x++){
               pict->data[0][i]=avpkt->data[fseek+j];
               j++;
               i++;
           }
           i+=skipSize;
       }

       /*Inform ffmpeg the output is a key frame and that it is ready for external usage*/
       pict->pict_type        = AV_PICTURE_TYPE_I;
       pict->key_frame        = 1;
       *got_frame=1;
       return 0;
    }