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• Revision 2de7cbe980 : Add second ref frame check back in rdcost hist Update best_inter_rd and best_in

  3 novembre 2013, par Jingning Han

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

  
  
  Add second ref frame check back in rdcost hist

  Update best_inter_rd and best_inter_ref_frame only in single ref
  frame case.

  Change-Id : Id56825b231a62d6852bd83811410c05a7569f715

• Adjusting video length to fit audio length in FFmpeg

  8 avril 2015, par Spreadys

  This has been driving me mad !
  I have video.avi, a raw uncompressed video with a duration of 6mins
  I have audio.wav, a raw uncompressed audio with a duration of 9mins

  I need to mux these together, but map the timing information from the audio.
  Using Vsync 2 I would hope that video frames get duplicated in order to do this.

  My current (failed) attempt is

  ffmpeg -i video.avi -i audio.wav
   c:v rawvideo -c:a copy
   vsync 2 -map 0:0,1:0 -map 1:0,1:0
  newvideo.avi

  My understanding is that the -map first designates what file:stream, and this is followed by the file:stream to be used for timing information.

  I have attempted all my usual research methods in an attempt to avoid asking but it is still resulting in the avi container holding two streams with the video length unchanged.
  If anyone can shed some light on my errors, I would be very grateful....or if you need further info - please ask !

  Thanks
  David

  Any guidance on what other information may promote some suggestions to where i’m going wrong also appreciated.
  Thanks

• Why is the ffmpeg `-vsync passthrough` option not extracting the same number of frames as shown in the printed info ?

  3 juin 2022, par aininja

  I am using ffmpeg to extract all the frames in a video. To get the timestamps of each frame, I'm using the -vf showinfo filter and matching the frame numbers. The problem is that sometimes the number of frames shown in the info doesn't match up with the number of frames extracted. Why could this be happening ? Is there some default output option that I need to change to avoid this ? Is this non-deterministic behavior a bug ?

  


  The commands used to extract and inspect the frames are :

  


  $ mkdir frames
$ ffmpeg -i video.mp4 -f image2 -vf showinfo -vsync passthrough -q:v 1 frames/%05d.jpg 2> info.txt
$ NUM_FRAMES_INFO=$(cat info.txt | grep pts_time | wc -l)
$ NUM_FRAMES_JPGS=$(ls frames/*.jpg | wc -l)
$ echo ${NUM_FRAMES_INFO} ?= ${NUM_FRAMES_JPGS}


  


  For most videos, this produces the correct outputs all the time. For some videos, however, there is a mismatch occasionally. Also worth mentioning is that MP4 videos are the only ones used and tested. These videos generally only had a single video stream in them.