Recherche avancée

Sur d’autres sites (9408)

• Ffmpeg deletes my file ?

  9 janvier 2018, par Melvin Roest

  Does anyone know why ffmpeg sometimes seemingly deletes my files ? It mostly happens when I put my laptop to sleep and wait for quite a bit after opening my Finder window.

  Here is an example command.

  ffmpeg -i  Rec\ 01-9-18\ 1.trec  -c:a aac -c:v libx264 tutorial.mp4

  It never happens when I don’t let my laptop sleep and open it immediately after finishing.

  I’m on Mac OS X.

• Not able to decode mp4 file using latest ffmpeg library : av_decode_video2

  8 février 2017, par suvirai

  I am writing a wrapper code around latest ffmpeg library. I am supplying MP4 files from local system. My problem is that I am unable to get any decoded frames when I use av_decode_video2(). The return value comes out to be negative. I have used av_read_frame() which returns 0. I googled about the problem I am facing but no where could I find the correct explanation. Please give me insight here. Pasting the pseudo code here.

      av_init_packet(avpkt);
  
      picture=av_frame_alloc();
  
      pFrameRGB=av_frame_alloc();
  
      codec = avcodec_find_decoder(CODEC_ID_H264);
  
      c= avcodec_alloc_context3(codec)
  
      avcodec_open2(decoderLibraryData->c, decoderLibraryData->codec, NULL)
  
      FormatContext = avformat_alloc_context();
  
      char *pUrl ="./1.MP4";
  
  
  
      iRet = avformat_open_input(atContext, pUrl, pFmt, NULL);
  
  
  
      if(FormatContext == NULL)
  
      {
  
          printf("could not assign any memory !!!!!!!!! \n");
  
      }
  
  
  
      avformat_find_stream_info(FormatContext, NULL);
  
  
  
  
  
      while(av_read_frame(FormatContext,avpkt) >= 0)
  
      {
  
  
  
        len = avcodec_decode_video2(c, picture, &got_picture,avpkt);
  
  
  
        printf("CODEC MANAGER len %d Frame decompressed %d \n",len,got_picture);
  
  
  
        if (len <= 0) 
  
        {
  
          return ERROR;
  
        }
  
      }
  
  }
  
  
  
  
  
  
  
          if(lastHeight != 0 && lastWidth != 0)
  
          {
  
              if(lastWidth != c->width || lastHeight != c->height )
  
              {
  
                  av_free(buffer);
  
                  buffer = NULL;
  
                  lastWidth = c->width;
  
                  lastHeight = c->height;
  
  
  
              }
  
          }
  
          else
  
          {
  
              lastWidth = c->width;
  
              lastHeight = c->height;
  
          }
  
          decodeFlag = 1;
  
          if(!buffer)
  
          {
  
              int numBytes;
  
              v_mutex_lock(globalCodecLock);
  
              switch(inPixFormat)
  
              {
  
              case RGB:
  
  
  
  
  
                  // Determine required buffer size and allocate buffer
  
                  numBytes=avpicture_get_size(PIX_FMT_RGB24, c->width, c->height);
  
  
  
                  buffer=(uint8_t *)av_malloc(numBytes*sizeof(uint8_t));
  
                  avpicture_fill((AVPicture *)pFrameRGB,buffer,PIX_FMT_RGB24,c->width, c->height);
  
  
  
                  if(cntxt)
  
                      sws_freeContext(cntxt);
  
  
  
                  cntxt = sws_getContext(c->width, c->height, c->pix_fmt,
  
                          c->width, c->height, PIX_FMT_RGB24, SWS_BICUBIC, NULL, NULL, NULL);
  
  
  
                  break;
  
  
  
              }
  
              v_mutex_unlock(globalCodecLock);
  
              if(cntxt == NULL)
  
              {
  
                  printf("sws_getContext error\n");
  
                  return ERROR;
  
              }
  
              }
  
  
  
          {
  
              sws_scale(cntxt, picture->data, picture->linesize, 0, c->height, pFrameRGB->data, pFrameRGB->linesize);
  
              if(rgbBuff)
  
              {
  
  
  
  
  
                  if(c->width <= *width && c->height <= *height)
  
                  {                   
  
                      saveFrame(pFrameRGB, c->width, c->height, rgbBuff,inPixFormat);
  
  
  
                      *width = c->width;
  
                      *height = c->height;
  
                      rs = SUCCESS;
  
                      break;
  
                  }
  
                  else
  
                  {
  
                      rs = VA_LOWBUFFERSIZE;
  
                  }
  
              }
  
              else
  
              {
  
                  rs = VA_LOWBUFFERSIZE;
  
              }
  
          }
  
          if(width)
  
          {
  
              *width = c->width;
  
          }
  
          if(height)
  
          {
  
              *height = c->height;
  
          }
  
          if(rs == VA_LOWBUFFERSIZE)
  
          {
  
              break;
  
          }

  I am getting the return value of av_read_frame as 0 but av_decode_video2 returns value in negative. I am not able to get any clue here.

• Specifying correct library to link in Xcode when multiple copies exist on search path

  23 avril 2015, par Robotbugs

  I am trying to compile a C++ file that depends on ffmpeg. I have spent a long time trying to fix all the link errors. I found that on the Mac it needs :

  libbz2.dylib
  
  libiconv.dylib
  
  libz.dylib
  
  libavcodec.a
  
  libavformat.a
  
  libswscale.a
  
  libswresample.a
  
  VideoDecodeAcceleration.framework
  
  CodeVideo.framework
  
  CoreFoundation.framework

  The problem I have is that I still get symbol link errors for libiconv even though the library is present in /usr/lib and all the other libraries in this directory are being found there. The compile line includes -liconv.2

  On searching around I found that the problem comes from there being two version of libiconv on my system. One is in /usr/lib and the other is in /opt/local/lib. The one in /usr/lib exports symbols that ffmpeg uses named like "_iconv_open", whereas the one in /opt/local/lib exports the same symbols with "lib" added, e.g. "_libiconv_open". It seems the compiler is picking up the /opt/local/lib library.

  How can I get Xcode to pick up the correct lib ?