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• getting very bad image after encoding

  20 avril 2012, par user1310596

  I am encoding images using avcodec_encode_video method and displaying them on subscriber demo of the Red5 media server.

  The problem i am facing is that all the images which are being displayed are totally distorted and nothing is clearly visible. I think something might be wrong with the pix_fmt set in avcodec context.
  Moreover image size is also quite large as 64000 bytes after encoding which I think is little weird
  Please give me solution of this problem. Any help is appreciated.

• Replaced Image Processing plugin with a more generic File Processing plugin.

  22 avril 2012, par Sebastian Tschan

  m README.md m index.html + js/jquery.fileupload-fp.js - js/jquery.fileupload-ip.js m js/jquery.fileupload-ui.js m js/main.js m package.json m test/index.html Replaced Image Processing plugin with a more generic File Processing plugin. The File Processing plugin exposes the "process" option, (...)

• sws_scale YUV —> RGB distorted image

  3 janvier 2015, par Sami susu

  I want to convert YUV420P image (received from H.264 stream) to RGB, while also resizing it, using sws_scale.
  The size of the original image is 480 × 800. Just converting with same dimensions works fine.
  But when I try to change the dimensions, I get a distorted image, with the following pattern :

  • changing to 481 × 800 will yield a distorted B&W image which looks like it’s cut in the middle
  • 482 × 800 will be even more distorted
  • 483 × 800 is distorted but in color
  • 484 × 800 is ok (scaled correctly).

  Now this pattern follows - scaling will only work fine if the difference between divides by 4.

  Here’s a sample code of the way that I decode and convert the image. All methods show "success".

  int srcX = 480;
  
  int srcY = 800;
  
  int dstX = 481; // or 482, 483 etc
  
  int dstY = 800;
  
  
  
  AVFrame* avFrameYUV = avcodec_alloc_frame();
  
  avpicture_fill((AVPicture *)avFrameYUV, decoded_yuv_frame, PIX_FMT_YUV420P, srcX , srcY);
  
  
  
  AVFrame *avFrameRGB = avcodec_alloc_frame();
  
  
  
  AVPacket avPacket;
  
  av_init_packet(&avPacket);
  
  avPacket.size = read; // size of raw data
  
  avPacket.data = raw_data; // raw data before decoding to YUV
  
  
  
  int frame_decoded = 0;
  
  int decoded_length = avcodec_decode_video2(g_avCodecContext, avFrameYUV, &frame_decoded, &avPacket);
  
  int size = dstX * dstY * 3;
  
  
  
  struct SwsContext *img_convert_ctx = sws_getContext(srcX, srcY, SOURCE_FORMAT, dstX, dstY, PIX_FMT_BGR24, SWS_BICUBIC, NULL, NULL, NULL);
  
  
  
  avpicture_fill((AVPicture *)avFrameRGB, rgb_frame, PIX_FMT_RGB24, dstX, dstY);
  
  sws_scale(img_convert_ctx, avFrameYUV->data, avFrameYUV->linesize, 0, srcY, avFrameRGB->data, avFrameRGB->linesize);
  
  
  
  // draws the resulting frame with windows BitBlt
  
  DrawBitmap(hdc, dstX, dstY, rgb_frame, size);
  
  
  
  sws_freeContext(img_convert_ctx);