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• Revision 6ddf1e152a : Fix int64_t to unsigned int conversion warnings Use unsigned int type to store

  28 août 2014, par Jingning Han

  Changed Paths :
   Modify /vp9/encoder/vp9_rdopt.c

  
  
  Fix int64_t to unsigned int conversion warnings

  Use unsigned int type to store the sse in the pixel domain. The
  precision is sufficient to handle sse of block size up to 64x64.
  The transform domain version however needs int64_t, since there is
  a transfer gain applied in the forward transformation that might
  cause unsigned int overflow.

  Change-Id : Ifef97c38597e426262290f35341fbb093cf0a079

• Revision 043d348aae : Reimplementation of loop filter This version of the loop filter supports non-4 :

  30 mai 2013, par John Koleszar

  Changed Paths :
   Modify /configure

  
   Modify /vp9/common/vp9_loopfilter.c

  
   Modify /vp9/common/vp9_loopfilter_filters.c

  
   Modify /vp9/common/vp9_rtcd_defs.sh

  
  
  Reimplementation of loop filter

  This version of the loop filter supports non-4:2:0 subsampling and
  a fourth plane, as well as changing the filtering order to be more
  friendly to hardware implementations.

  The filters are applied first to all vertical edges within the
  64x64 SB, followed by the top horizontal edge and any internal
  horizontal edges. Since filtering is applied on each 4x4 edge
  serially, a dependency is created from filtering one block edge
  to the next. It would be possible to remove this depencnecy by
  building all filtering decisions from the unfiltered
  reconstruction data.

  Change-Id : I08f3e9683eb7bded8a76651cbc50fc0dfdd05fa7

• A random pixel on a keyframe. (ffmpeg)

  5 juin 2013, par Chris Russo

  Hello folks of SO !

  We're trying to do some very small and simple code in PHP to generate a variation of a video, using always the same file.

  The script would have to make a small pixel mark, on random or specific frame of the video file, and this would have to be streamed in real time.

  Here's some pseudo code to explain my idea :

  $frame = $_GET[frame];
  
  $videofile = 'video.avi';
  
  
  
  make_random_red_pixel_mark($videofile, $frame);

  Does anyone know if this is possible using ffmpeg ? As well, it is of extreamly importance for us, to execute this procedure as fast as possible.

  A solution that would imply reprocessing the whole video, won't be useful for our purposes. It should be something like a closed caption, or a quick image / overlay filter that could be applied without an entire video reprocessing. As well, we can't put the overlay using Javascript nor any HTML approach, since the actual manipulation has to be on the video file itself.

  The quality, and framerate of the original video, should be kept intact. Perhaps some other PHP module or software that could be execute from PHP using an exec() ?

  Any recommendation ?

  Thanks in advance !!
  Chris C. Russo

  More information :

  1) It's possible for us to apply this procedure on any frame we want to, so we could use a "keyframe" in order to avoid the decoding and reencoding of an entire GOP.

  2) As previously stated, the video stream would have to flow in real time.