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• dxva2_vc1 : fix signaling of intensity compensation values

  12 décembre 2013, par Hendrik Leppkes

  dxva2_vc1 : fix signaling of intensity compensation values
  lumscale/lumshift don’t get reset back to their default values if
  
  intensity compensation is not active, and a wrong signaling here can
  
  cause playback issues.
  Signed-off-by : Michael Niedermayer <michaelni@gmx.at>
  

  • [DH] libavcodec/dxva2_vc1.c

• FFMPEG decoding artifacts between keyframes

  13 avril 2015, par OddlyOrdinary

  I’m currently experiencing artifacts when decoding video using ffmpegs api. On what I would assume to be intermediate frames, artifacts build slowly only from active movement in the frame. These artifacts build for 50-100 frames until I assume a keyframe resets them. Frames are then decoded correctly and the artifacts proceed to build again.

  One thing that is bothering me is I have a few video samples that are 30fps(h264) that work correctly, but all of my 60fps videos(h264) experience the problem.

  I don’t currently have enough reputation to post an image, so hopefully this link will work.
  http://i.imgur.com/PPXXkJc.jpg

  int numBytes;
  
  int frameFinished;
  
  AVFrame* decodedRawFrame;
  
  AVFrame* rgbFrame;
  
  
  
      //Enum class for decoding results, used to break decode loop when a frame is gathered
  
  DecodeResult retResult = DecodeResult::Fail;
  
  
  
  decodedRawFrame = av_frame_alloc();
  
  rgbFrame = av_frame_alloc();
  
  if (!decodedRawFrame) {
  
      fprintf(stderr, "Could not allocate video frame\n");
  
      return DecodeResult::Fail;
  
  }
  
  
  
  numBytes = avpicture_get_size(PIX_FMT_RGBA, mCodecCtx->width,mCodecCtx->height);
  
  uint8_t* buffer = (uint8_t *)av_malloc(numBytes*sizeof(uint8_t));
  
  
  
  avpicture_fill((AVPicture *) rgbFrame, buffer, PIX_FMT_RGBA, mCodecCtx->width, mCodecCtx->height);
  
  
  
  AVPacket packet;
  
  
  
  while(av_read_frame(mFormatCtx, &packet) >= 0 && retResult != DecodeResult::Success)
  
  {
  
      // Is this a packet from the video stream?
  
      if (packet.stream_index == mVideoStreamIndex)
  
      {
  
          // Decode video frame
  
          int decodeValue = avcodec_decode_video2(mCodecCtx, decodedRawFrame, &frameFinished, &packet);
  
  
  
          // Did we get a video frame?
  
          if (frameFinished)// && rgbFrame->pict_type != AV_PICTURE_TYPE_NONE )
  
          {
  
              // Convert the image from its native format to RGB
  
              int SwsFlags = SWS_BILINEAR;
  
              // Accurate round clears up a problem where the start
  
                              // of videos have green bars on them
  
              SwsFlags |= SWS_ACCURATE_RND;
  
              struct SwsContext *ctx = sws_getCachedContext(NULL, mCodecCtx->width, mCodecCtx->height, mCodecCtx->pix_fmt, mCodecCtx->width, mCodecCtx->height, 
  
                  PIX_FMT_RGBA, SwsFlags, NULL, NULL, NULL);
  
              sws_scale(ctx, decodedRawFrame->data, decodedRawFrame->linesize, 0, mCodecCtx->height, rgbFrame->data, rgbFrame->linesize);
  
  
  
              //if(count%5 == 0 && count < 105)
  
              //  DebugSavePPMImage(rgbFrame, mCodecCtx->width, mCodecCtx->height, count);
  
  
  
              ++count;
  
              // Viewable frame is a struct to hold buffer and frame together in a queue
  
              ViewableFrame frame;
  
              frame.buffer = buffer;
  
              frame.frame = rgbFrame;
  
              mFrameQueue.push(frame);
  
  
  
  
  
              retResult = DecodeResult::Success;
  
  
  
              sws_freeContext(ctx);
  
          }
  
      }
  
  
  
      // Free the packet that was allocated by av_read_frame
  
      av_free_packet(&packet);
  
  }
  
  
  
  // Check for end of file leftover frames
  
  if(retResult != DecodeResult::Success)
  
  {
  
      int result = av_read_frame(mFormatCtx, &packet);
  
      if(result < 0)
  
          isEoF = true;
  
      av_free_packet(&packet); 
  
  }   
  
  
  
  // Free the YUV frame
  
  av_frame_free(&decodedRawFrame);

  I’m attempting to build a queue of the decoded frames that I then use and free as needed. Is my seperation of the frames causing the intermediate frames to be decoded incorrectly ? I also break the decoding loop once I’ve successfully gathered a frame(Decode::Success, most examples I’ve seen tend to loop through the whole video.

  All codec contect, video stream information, and format contexts are setup up exactly as shown in the main function of https://github.com/chelyaev/ffmpeg-tutorial/blob/master/tutorial01.c

  Any suggestions would be greatly appreciated.

• Anomalie #3379 (Nouveau) : Bug affichage compatibilité plugin

  1er février 2015, par Maïeul Rouquette

  J’avais un plugin dont le paquet.xml avait :

  
  J’ai essayé d’activé avec une version d’agenda ultérieure et j’ai obtenu

  Nécessite le plugin AGENDA en version 3.0.1 minimum.

  Or le problème n’est ici pas dans la version minimum, mais dans la version maximum. En outre il ne s’agit pas d’une nécessité mais d’une compatibilité.