[Libav-user] WG: mov demuxer: avformat_seek_file with AVSEEK_FLAG_BYTE

[Beni Weine]

Hi all,

We need to improve the seeking 
capabilities (performance) in our video player. 
The video player concurrently 
manages 5 
different video files (MP4), 
and plays them 
in a time synchronized manner. 
Each video file has a time 
index file (proprietary) 
which includes 
among other things a time stamp and 
the corresponding byte position of the H.
264 data (I frame). 

Pure time-based 
seeking is not an option due to performance reasons. 

The same player can 
handle MPEG-2 
file. They come with a video 
time index file as well. 
We have amazing results with bytes-wise seeking 
(calling 
avformat_seek_file with 
AVSEEK_FLAG_BYTE). 
It seems that the mpegtsraw demuxer (libavformat/mpegts.c) is 
doing that 
pretty good. 

Different 
story with the mov demuxer: 
To me it looks that the current implementation of 

libavformat/mov.c does not support byte-
wise seeking. 
Having a look into the mov.c confirms my impression. 

It there 
a possibility that this feature will be 
added to 
the mov demuxer any time soon? 

Thanks and best regards,
Beni