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• Multiple HD video streaming using ffmpeg

  24 mars 2014, par user1199722

  I am trying to stream HD rtsp streams (1080p) from IPcamera over LAN and displaying it.
  streaming is done using openRTSP and decoding is done using ffmpeg.
  For a single frame decoding takes 30-40ms and displaying it on the QTwindow takes another 6-7 ms. When streaming more than 2-3 cameras the whole system is not able to handle it.Can anybody tell me that what could be the best method to approach the problem. Right now I am using a machine with Pentium 64-bit processor with ubuntu 12.04LTS.

  Should I go for Graphics card ? If so which would be better for ffmpeg hardware acceleration ?
  If I have to display 16 videos, Will one graphics card sufficient ?

• Revision 516d0b1180 : Set up early RD cost check for NEWMV in non-RD mode decision flow This commit e

  4 avril 2014, par Jingning Han

  Changed Paths :
   Modify /vp9/encoder/vp9_pickmode.c

  
  
  Set up early RD cost check for NEWMV in non-RD mode decision flow

  This commit estimates the motion vector rate cost right after full
  pixel motion search. It combines this and the mode cost and compares
  the corresponding rate-distortion cost. If it is already above the
  current best one, skip the rest sub-pixel motion search and modeling
  process. For pedestrian_area 1080p at 4000 kpbs, the speed -5 runtime
  goes down from 39425 ms -> 38399 ms.

  Change-Id : If4cd7119fd6c266798d5cf1d19d19ab425e52a26

• Revision d36852b702 : Add encoding option —static-thresh This option exists in VP8, and it was rewri

  11 juillet 2013, par Yunqing Wang

  Changed Paths :
   Modify /vp9/encoder/vp9_encodeframe.c

  
   Modify /vp9/encoder/vp9_rdopt.c

  
  
  Add encoding option —static-thresh

  This option exists in VP8, and it was rewritten in VP9 to support
  skipping on different partition levels. After prediction is done,
  we can check if the residuals in the partition block will be all
  quantized to 0. If this is true, the skip flag is set, and only
  prediction data are needed in reconstruction. Based on DCT's energy
  conservation property, the skipping check can be estimated in
  spatial domain.

  The prediction error is calculated and compared to a threshold.
  The threshold is determined by the dequant values, and also
  adjusted by partition sizes. To be precise, the DC and AC parts
  for Y, U, and V planes are checked to decide skipping or not.

  Test showed that
  1. derf set :
  when static-thresh = 1, psnr loss is 0.666% ;
  when static-thresh = 500, psnr loss is 1.162% ;
  2. stdhd set :
  when static-thresh = 1, psnr loss is 1.249% ;
  when static-thresh = 500, psnr loss is 1.668% ;

  For different clips, encoding speedup range is between several
  percentage and 20+% when static-thresh <= 500. For example,
  clip bitrate static-thresh psnr time
  akiyo(cif) 500 0 48.923 5.635s(50f)
  akiyo 500 500 48.863 4.402s(50f)

  parkjoy(1080p) 4000 0 30.380 77.54s(30f)
  parkjoy 4000 500 30.384 69.59s(30f)

  sunflower(1080p) 4000 0 44.461 85.2s(30f)
  sunflower 4000 500 44.418 78.1s(30f)

  Higher static-thresh values give larger speedup with larger
  quality loss.

  Change-Id : I857031ceb466ff314ab580ac5ec5d18542203c53