[MPlayer-users] specify audio-video sync method

Jan Mashat jan.mashat at factory.co.hu
Mon Oct 18 14:50:40 CEST 2010


Unfortunately the videos I'm trying to play are somehow missing these  
time-stamps, so trying to seek in mplayer with an -audiofile always  
resets the audio to the beginning (with a "[mpeg2video @  
0xa04dc0]warning: first frame is no keyframe" error). VLC doesn't play  
the audio at all, giving a "demux doesn't like DEMUX_GET_TIME" error.  
Full details here: http://lists.mplayerhq.hu/pipermail/mplayer-users/2010-October/081243.html

QuickTime, on the other hand, has an internal logic of treating all  
files as .MOV and creates a sample table from beginning to end in  
memory.
http://openradar.appspot.com/6008501

This way QuickTime is able to play 720x576 videos, but it chokes on  
1920x1080 videos (probably due to invalid FOURCC).

Jan


On Oct 18, 2010, at 12:23 PM, Carl Eugen Hoyos wrote:

> Jan Mashat <jan.mashat <at> factory.co.hu> writes:
>
>> Is there any way to specify how the video and audio (-audiofile) sync
>> up with each other?
>> By default, mplayer plays both on their individual time scales,
>> ignoring if one finishes before the other.
>>
>> Quicktime, on the other hand, synchronizes the video to the audio,
>> doubling or dropping video frames in order to make both files finish
>> at the same time.
>> Can this behavior be replicated in mplayer?
>
> How does QuickTime know in advance how long audio (and video) will  
> play?
>
> Audio has one "correct" speed that is specified by bit-rate and  
> sample-rate.
> It's not that different for video: The decoder provides time-stamps  
> that specify
> when frames should be shown and it should be the player's goal to  
> present the
> frames at the right moment.
>
> Or do I misunderstand you?
>
> Carl Eugen
>
> _______________________________________________
> MPlayer-users mailing list
> MPlayer-users at mplayerhq.hu
> https://lists.mplayerhq.hu/mailman/listinfo/mplayer-users



More information about the MPlayer-users mailing list