Recherche avancée

Sur d’autres sites (5720)

• libav MPEGTS demuxing - handle loop/discontinuity

  28 septembre 2021, par Michal Artazov

  I'm writing a video/audio player that uses libav/ffmpeg for demuxing and decoding MPEGTS streams over UDP. One problem that I'm dealing with is that sometimes the stream is looping and when it loops, my player breaks down.

  


  The issue is that once the stream loops, the new packets have widely different dts/pts. My player is relying on pts for video - audio synchronisation so it's important that I can handle pts properly.

  


  Whenever the server loops the stream, it sends a discontinuity flag, which I can confirm is being correctly received by libav mpegts demuxer (I did some digging in the code and inspected the debug logs). However, it seems to me that the demuxer doesn't act on the discontinuity flag much. In other words, from the point of view of the user I can't tell that there's a discontinuity, apart from the dramatic jump in dts/pts.

  


  Is there a way I can reliably tell that there was a discontinuty so I can recalculate my timestamps and continue playback smoothly ?

  


• Merge commit ’04763c6f87690b31cfcd0d324cf36a451531dcd0’

  18 mars 2017, par Clément Bœsch

  Merge commit ’04763c6f87690b31cfcd0d324cf36a451531dcd0’
  * commit ’04763c6f87690b31cfcd0d324cf36a451531dcd0’ :
  
    h264_direct : use the reference mask from the actual reference
  This commit is a noop, see d8151a7e944aea52d167571badc247c8d9972847
  Merged-by : Clément Bœsch <u@pkh.me>
  

• ffmpeg - prop flicker removal works but ffmpeg insists on changing framerate [closed]

  28 avril 2023, par Mutley Eugenius

  I have been researching how to use FFmpeg to do some fantastic wizardry on my cockpit videos to remove the dramatically distracting propeller, but after many hours now I cannot seem to find a way to get the program to stop stripping more than half the frames. The source video file is 1920 x 1080 @ 60fps and I believe I have my offset right (1/60= 0.0166) but the output video is always coming out at 25 fps. Can't see what element in the code is telling it to do that, or how to change it.

  


  Here's my file :

  


  https://drive.google.com/file/d/1VPttH4PHgUr0uzmsbl4Bcyg5_gAixblA/view?usp=sharing

  


  Here's my code :

  


  ffmpeg -i G:\PropFlicker.mp4 -itsoffset 0.01666 -i G:\PropFlicker.mp4 -filter_complex color=0x202020:s=1920x1080:d=24[mask];[mask][0][1]maskedmax=[out] -map [out] -crf 10 G:\PropNoFlicker.mp4


  


  I have tried adding -r 60 which gives me a 60 fps output file, but the video is still being processed at 25 and it just adds in duplicated frames after processing to pad it out to 60. The rendering shows more dropped frames than rendered frames by about a 3 to 2 ratio which matches frame drops from 60 to 25. I lose my shot fluidity and I get flickery artifacts

  


  What am I missing to get the flicker removal processing done at 60 fps and the output file rendered at 60 fps with the original smoothness ?

  


  I'm also not sure what the :d=24 is doing. I tried d=60, but it made no difference.

  


  I copied original code that I found in this link :

  


  text