[FFmpeg-user] synchronisation problem on encoding video files
ffmpeg at frank.haefemeier.eu
Tue Jan 29 21:34:40 CET 2013
Am Sonntag, den 27.01.2013, 22:38 +0200 schrieb Andrei Danila:
> I am writing to you guys to see if somebody can help us figure out what are we doing wrong. We are working on a project that involves users uploading video files and then we make it available to viewers in different formats. A tube website :). No matter what we try we keep getting the same problem. The result files all have a de-syncronisation of 0.3-1s between sound and video. Here is the command line that we use:
> /usr/local/bin/ffmpeg -y -i input -isync -async 1 -f mp4 -threads 0 -b:v 2500k -s 1280x720 -c:v libx264 -pass 1 -preset veryslow -tune film -r 24000/1001 -an -map_metadata -1 output
> /usr/local/bin/ffmpeg -y -i input -isync -async 1 -f mp4 -threads 0 -b:v 2500k -s 1280x720 -c:v libx264 -pass 2 -preset veryslow -tune film -r 24000/1001 -c:a libfaac -b:a 128k -ar 44100 -ac 2 -map_metadata -1 output
> Is it something that we are doing wrong? Is there any setting that we have overlooked?
IMHO a better way to synchronize audio and video is to use filter like
'asyncts' (now deprecated) or 'avresample' (replaceent of avsyncts).
Sorry, but I can't tell you yet how to use the new filter. I am in the
same situation to sync audio and video and have to figure out how to do
it with the new filter.
If you search on the list you will find some mails related to this
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