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• How to accurately match an image to a video frame and exit with ffmpeg

  10 avril 2020, par Hans J

  In Bash,
I am trying to match an image to a frame in ffmpeg. I also want to exit the ffmpeg process when the match is found. Here is a (simplified version) of the code currently :

  



  ffmpeg --hide_banner -ss 0 -to 60 \
-i "video.mp4" -i "image.jpg" -filter_complex \
"blend=difference, blackframe" -f null - null 2>log.txt &
pid=$!
trap "kill $pid 2>/dev/null" EXIT
while kill -0 $pid 2>/dev/null; do
     # (grep command to monitor log file)
     # if grep finds blackframe match, return blackframe time
done


  



  To my understanding, if the video actually contains a blackframe I will get a false-positive. How can I effectively mitigate this ?

  



  While this is unnecessary to answer the question, I would like to exit the ffmpeg process without having to use grep to constantly monitor the log file, instead using pure ffmpeg

  



  Edit : I say this because while I understand the blend filter is computing the difference, I am getting a false positive on a blackframe in my video and I don't know why.

  



  Edit : A possible solution to this issue is to not use blackframe at all, but psnr (Peak Signal to Noise Ratio) but normal usage is by comparing two videos frame by frame, and I don't know how to effectively use it with an image as input.

  


• Revision 1521eb8ba9 : ads2armasm_ms : Match the indentation of the previous line Instead of hardcoding

  20 mars 2014, par Martin Storsjo

  Changed Paths :
   Modify /build/make/ads2armasm_ms.pl

  
  
  ads2armasm_ms : Match the indentation of the previous line

  Instead of hardcoding a certain indentation, use the regexp to
  provide similar indentation for the new line as well.

  Change-Id : Iacb2621b35ce7e1aa3980c1603b8e3ab02d98a35

• avformat : fix orig_pos type to match pkt->pos

  23 avril 2013, par Paul B Mahol

  avformat : fix orig_pos type to match pkt->pos