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• Add jQuery style guide link

  6 mai 2013, par nschonni

  Add jQuery style guide link

• lavf : Add an option for avoiding negative timestamps

  26 septembre 2012, par Michael Niedermayer

  lavf : Add an option for avoiding negative timestamps
  This is the same logic as is invoked on AVFMT_TS_NEGATIVE,
  
  but which can be enabled manually, or can be enabled
  
  in muxers which only need it in certain conditions.
  Also allow using the same mechanism to force streams to start
  
  at 0.
  Signed-off-by : Martin Storsjö <martin@martin.st>
  

  • [DH] doc/APIchanges
  • [DH] libavformat/avformat.h
  • [DH] libavformat/mux.c
  • [DH] libavformat/options_table.h
  • [DH] libavformat/version.h

• Given 2 input videos of different lengths at 60 FPS with multiple common sections in between, what is the best way to sync them at the common section ?

  27 janvier 2024, par PirateApp

  
input vs output

  


  

  • In my actual case, there are 4 videos (basically gaming videos recorded from 4 different machines)

  


  • Each video may start or end at different duration (manually controlled by people starting and stopping recording and therefore their lengths vary slightly)

  


  • Each video has one or more common sections (basically a cutscene playing at the same time)

  


  • The distance between the common sections is the same in every video

  


  • How do I sync the videos at the common section ?

  


  • Basically I want to create a split screen video such that the common part plays at the same time on all the sub parts of the video

  


  • Keep in mind that the common sections wont be EXACTLY equal (because of graphics differences between machines but highly similar like dx9 vs dx11 or gamma)
What have I tried ?

  


  • Naive approach

  


  • Start video 1 at 0, start video 2 at 0.017, render the whole thing and check if it is in sync

  


  • Start video 1 at 0, start video 2 at 0.033, render the whole thing and check if it is in sync

  


  • Basically loop through the length of the video at each frame interval, render the full video and check if we get a synced version

  


  


  This sounds like a terrible idea honestly

  


    for (t1 in length of video a) {
    for (t2 in length of video b) {
       render a video with a and b starting at t1, t2 respectively
       increment t2 by 0.017 for b
    }
    increment t1 by 0.017 for a
  }


  


  Final output with 4 videos should look like this all synced at common sections


  


  Any better ideas ?