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• h264 : Allow stream and container cropping at the same time

  8 mars 2015, par Vittorio Giovara

  h264 : Allow stream and container cropping at the same time
  The container cropping is applied only when difference is within 16
  
  pixels, and the smallest value between the two is chosen.
  Bug-Id : 383
  
  Signed-off-by : Vittorio Giovara <vittorio.giovara@gmail.com>
  

  • [DH] libavcodec/h264_slice.c

• Real-time streaming of rawdata images to Android with FFMPEG

  29 juillet 2015, par Philies

  CONDITIONS

  I have an C++ server (Linux) and want to transmit rawdata images (RGB, 32bit) to an Android device in real-time.
  The server generates the rawdata images (with or without bitmap header) continuously every x miliseconds. Now, I want to put the rawdata images into a stream and transmit them without much delay to the Android client.

  I’ve chosen FFMPEG for this kind of job.

  The input for FFMPEG should be the rawdata images, which are generated just in time. The output should be an rtsp stream (h264 or is another format better ?).
  On client side I will play the stream with the Android MediaPlayer. That works for a RTSP url like rtsp ://184.72.239.149/vod/mp4:BigBuckBunny_115k.mov

  ---

  PREVIOUS APPROCH :

  I’ve installed FFMPEG on my server.

  Depending on this question : https://ffmpeg.org/pipermail/ffmpeg-user/2013-April/014617.html ... here is my FFMEG command :

  ffmpeg -an -f rawvideo -vcodec rawvideo -pix_fmt rgb32 -r 10 -i -vcodec libx264 -r 30 -tune zerolatency -preset ultrafast -bsf:v h264_mp4toannexb -f mpegts udp://192.168.1.20:1234

  Explanation of the parameters :

  • -an = ignore audio
  • -report = log file in current directory

  INPUT :

  • -f = rawvideo (video format)
  • -vcodec = rawvideo (video codec)
  • -pix_fmt = rgb32
  • -r = 10 (frame rate)

  OUTPUT :

  • -vcodec = libx264
  • -r = 30 (frame rate)
  • -bsf:v = h264_mp4toannexb
  • -f = mpegts udp ://192.168.1.20:1234

  ---

  C++ Server Code Snippet :

  /* -------  Get image rawdata from source ------- */
  
  ...
  
  /* -------  Create image header which fits to the image rawdata ------- */
  
  ...
  
  
  
  /* ------- Store the picture local (not necessary?) ------- */
  
  FILE *f;
  
  f = fopen("/home/philies/test.bmp","wb");
  
  
  
  //Write Bitmap Headers
  
  fwrite(&imageFileHeader,1,sizeof(imageFileHeader),f);
  
  fwrite(imageInfoHeader,1, imageInfoHeader,f);
  
  
  
  //Write Bitmap Rawdata
  
  fwrite(lastImage.GetBitmapRawData(),1,imageSize,f);
  
  
  
  
  
  —> ffmpeg ???

  ---

  PROBLEMS/QUESTIONS :

  1. How can I specify the rawvideo of the ffmpeg command respectively how can I specify my bitmap rawdata (with or without header ?) as the input of the FFMPEG ?

  2. Is the FFMPEG command correct ?

  If I fire the FFMPEG command in the terminal I get this error :

  vcodec : no such file or directory

  EDIT :
  In the first step, I will open the udp stream with the VLC player on my Android device. After that I will set up a FFserver to create a RTSP stream

• Revision 3b2e73b9a4 : Remove tx cache and speed up tx size selection 1. The RD scores obtained during

  29 juillet 2015, par Yunqing Wang

  Changed Paths :
   Modify /vp9/encoder/vp9_context_tree.h

  
   Modify /vp9/encoder/vp9_encodeframe.c

  
   Modify /vp9/encoder/vp9_rdopt.c

  
  
  Remove tx cache and speed up tx size selection

  1. The RD scores obtained during the tx size selection were stored in the
  tx cache, and used to help make the tx decision for the following frames.
  This wasn’t used anymore in VP9 encoder. Recovered the related decision
  making code from 1.5+ years ago, and borg tests didn’t show any quality
  gain. This patch removed it to lower the complexity.

  2. An optimization was done after the above refactoring. If the tx_mode
  is not TX_MODE_SELECT, we only need to test the chosen tx size instead
  of all posible tx sizes. This gave a 1.5% average speed gain at speed 2,
  and a 1% average speed gain at speed 3.

  Change-Id : Id8cd650e066a8cef33829d8c15388a8138adc78c