[FFmpeg-user] Audio Video Lip Sync Problem - IPhone mov

Gagandeep Bawa gagandeep.bawa at ironroad.com
Fri Dec 2 10:47:48 CET 2011

Hi Guys,

I am compressing IPhone recorded mov file in to mpeg4 file with in my
IPhone app itself. For this i compiled ffmpeg libraries for IPhone and
doing compression programmatically using ffmpeg libraries with in IPhone
app. Everything working fine except video audio lip sync problem. Video
seems to be running slow and not proper sync with audio, however output
file duration comes correct same as it was in original file. I checked for
12 sec video and 1 min video both. I am setting 15 frame rate for video. I
am just compressing video frames and not compressing audio frames, i am
writing audio frames as it is in out put stream.

It would be great if some one can help me to resolve this audio video lip
sync problem. I need to fix this programmatically only not from ffmpeg
command line options.


Thanks & Regards,

More information about the ffmpeg-user mailing list