Nicolas George in gmane.comp.video.ffmpeg.devel (Tue, 16 Jul 2013 17:28:55 +0200):
L'octidi 28 messidor, an CCXXI, Jan Ehrhardt a écrit :
It might be a crappy OS (Windows), which cannot be configured better. But it perfectly explains the speed decrease (from 17 to 27 seconds) when the only thing you do is turn FFMpeg's logging on.
No, it does not, since the amount of ffmpeg's log messages is negligible. Please see the rest of my previous message for things that matter.
Two command lines: ffmpeg.exe \ -i U:\MP_ROOT\100PNV01\SD00004.MP4 \ -i U:\MP_ROOT\100PNV01\SD00005.MP4 \ -filter_complex " \ [0:a]asetpts=PTS-STARTPTS[a0]; \ [1:a]asetpts=PTS-STARTPTS[a1]; \ [a0][a1]concat=n=2:v=0:a=1[a]; \ [a]volumedetect[am]" -map [am] \ -f null -y /dev/null Execution time: 16.765 seconds. ffmpeg.exe \ -i U:\MP_ROOT\100PNV01\SD00004.MP4 \ -i U:\MP_ROOT\100PNV01\SD00005.MP4 \ -filter_complex " \ [0:a]asetpts=PTS-STARTPTS[a0]; \ [1:a]asetpts=PTS-STARTPTS[a1]; \ [a0][a1]concat=n=2:v=0:a=1[a]; \ [a]volumedetect[am]" -map [am] \ -report -f null -y /dev/null Execution time: 27.154 seconds Please tell me where I go wrong. And/or guide me to a quicker volumedetect an a concatenated audio track. Jan