View Full Version : audi/video synchronization problem in qtopia

19th February 2008, 06:10

i am new to this qt forum. i am porting MPEG4 hardware decoder in qtopia's video application. i have already ported(implemented) MPEG4 hardware decoder in place of software decoder. and i am able to play only video file perfectly but not able to play audio video file. but if i comment sync function it is playing this file but audio and video is not in sync.
i am updating the pts value for video correctly. i have not touched audio part. and now i am totally blank not able to find the problem.

i am using "qtopia-free-2.2.0" version of qtopia. can anubody tell me,
in videocodeccontext.cpp file,

bool VideoCodecContext::syncToTimeStamp( long audioTS )

function they are setting some AVSlack value. the line is like this

const int AVSyncSlack = 100; // 100 ms slack
on what basis they are selecting this value as 100ms?

please, anybody tells me how synchronization is acheived in the qtopia media player (video application).

thanks in advance,