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• Revision c389b37bb4 : Substantial reworking of code for arf and kf groups. Substantial restructuring

  15 août 2014, par Paul Wilkins

  Changed Paths :
   Modify /vp9/encoder/vp9_firstpass.c

  
   Modify /vp9/encoder/vp9_firstpass.h

  
   Modify /vp9/encoder/vp9_ratectrl.c

  
   Modify /vp9/encoder/vp9_ratectrl.h

  
  
  Substantial reworking of code for arf and kf groups.

  Substantial restructuring of the way we estimate
  the rate of decay in prediction quality and determine
  the arf interval and amount of boost used.

  Also other changes to support moving to a lower first pass
  Q which exposes some new features and allows us to better
  distinguish genuinely static blocks from low motion or noisy
  blocks.

  Net gains now visible on all the test sets with std-hd PSNR up
  1.87%. There are still some bad outlier cases but most of these
  are low motion or slide show type content where the metrics
  are already high at any given rate. The best + case is up by
  more than 10%.

  Change-Id : I18e25170053bdf3188f493ff8062f48a74515815

• FFMPEG sws_scale Crash on Android

  22 septembre 2014, par Jimmy

  I have an app that convert images to video, in Google Play I see the following crash (which the only details I get is the name of the function and I don’t understand the rest) :

  backtrace:
  
  #00 pc 0000cc78 /data/app-lib/com.myapp-1/libswscale.so (sws_scale+204)
  
  #01 pc 000012af /data/app-lib/com.myapp-1/libffmpeg.so (OpenImage+322)
  
  
  
  code around pc:
  
  79065c58 e58d8068 e58d2070 e58d3074 059d00b0 

  The code point to the function sws_scale, the code works almost all the time on my device (Nexus 5) but I see a lot of reports even with the same device with that issue. Any idea why this could happen ?

  AVFrame* OpenImage(const char* imageFileName, int W_VIDEO, int H_VIDEO, int* numBytes)
  
  {
  
      AVFormatContext *pFormatCtx;
  
      AVCodecContext *pCodecCtx;
  
      AVCodec *pCodec;
  
      AVFrame *pFrame;
  
      int frameFinished;
  
      uint8_t *buffer;
  
      AVPacket packet;
  
      int srcBytes;
  
  
  
      AVFrame* frame2 = NULL;// scaled frame
  
      uint8_t* frame2_buffer;
  
      struct SwsContext *resize;
  
  
  
      if(av_open_input_file(&pFormatCtx, imageFileName, NULL, 0, NULL)!=0)
  
      {
  
          LOGI("Can't open image file '%s'\n", imageFileName);
  
          return NULL;
  
      }
  
      //dump_format(pFormatCtx, 0, imageFileName, 0);
  
      if (av_find_stream_info(pFormatCtx) < 0)
  
      {
  
          LOGI("Can't find stream info.");
  
          return NULL;
  
      }
  
      pCodecCtx = pFormatCtx->streams[0]->codec;
  
      pCodecCtx->pix_fmt = PIX_FMT_YUV420P;
  
  
  
      // Find the decoder for the video stream
  
      pCodec = avcodec_find_decoder(pCodecCtx->codec_id);
  
      if (!pCodec)
  
      {
  
          LOGI("Codec not found\n");
  
          return NULL;
  
      }
  
  
  
      // Open codec
  
      if(avcodec_open(pCodecCtx, pCodec)<0)
  
      {
  
          LOGI("Could not open codec\n");
  
          return NULL;
  
      }
  
      pFrame = avcodec_alloc_frame();
  
      if (!pFrame)
  
      {
  
          LOGI("Can't allocate memory for AVFrame\n");
  
          return NULL;
  
      }
  
  
  
      // Determine required buffer size and allocate buffer
  
      srcBytes = avpicture_get_size(PIX_FMT_YUV420P, pCodecCtx->width, pCodecCtx->height);
  
      buffer = (uint8_t *) av_malloc(srcBytes * sizeof(uint8_t));
  
      avpicture_fill((AVPicture *) pFrame, buffer, PIX_FMT_YUV420P, pCodecCtx->width, pCodecCtx->height);
  
  
  
      // Read frame
  
      if (av_read_frame(pFormatCtx, &packet) >= 0)
  
      {
  
          int ret;
  
  //      if(packet.stream_index != 0)
  
  //          continue;
  
          ret = avcodec_decode_video2(pCodecCtx, pFrame, &frameFinished, &packet);
  
          if (ret > 0)
  
          {
  
              //LOGI("Frame is decoded, size %d\n", ret);
  
              pFrame->quality = 4;
  
  
  
              // Create another frame for resized result
  
              frame2 = avcodec_alloc_frame();
  
              *numBytes = avpicture_get_size(PIX_FMT_YUV420P, W_VIDEO, H_VIDEO);
  
              frame2_buffer = (uint8_t *)av_malloc(*numBytes * sizeof(uint8_t));
  
              avpicture_fill((AVPicture*)frame2, frame2_buffer, PIX_FMT_YUV420P, W_VIDEO, H_VIDEO);
  
  
  
              // Get resize context
  
              resize = sws_getContext(pCodecCtx->width, pCodecCtx->height, PIX_FMT_YUV420P, W_VIDEO, H_VIDEO, PIX_FMT_YUV420P, SWS_BICUBIC, NULL, NULL, NULL);
  
  
  
              // frame2 should be filled with resized samples
  
              ret = sws_scale(resize, (const uint8_t* const*)pFrame->data, pFrame->linesize, 0, pCodecCtx->height, frame2->data, frame2->linesize);
  
              sws_freeContext(resize);
  
          }
  
          else
  
              LOGI("Error [%d] while decoding frame: %s\n", ret, strerror(AVERROR(ret)));
  
      }
  
      av_free(pFrame);
  
      av_free_packet(&packet);
  
      avcodec_close(pCodecCtx);
  
      //av_free(pCodecCtx);
  
      av_close_input_file(pFormatCtx);
  
      return frame2;
  
  }

• Get_iplayer not converting to MP4 [closed]

  16 juin 2022, par PhilDunford

  get_iplayer

  


  I know that this is an old piece of code, but it still does a great job.

  


  In the last week or so it's stopped converting the .ts files to .mp4. I've seem this mentioned elsewhere, but no solution. I think the key line among many error messages may be 'unable to determine ffmpeg version'.

  


  I assume the BBC has done something to break it (this has happened many times before).

  


  Needs someone much cleverer than me to fix it. Does anyone still update the code or know a work around ?