On Wed, 25 Aug 2004, Anne Wilson wrote: > I took the problem to the xine mailing list, and after making the file > available for download I got this reply: > <quote> > The problem is caused by the video PTS values. > xine tries to predict what the correct PTS value is. > Then some video frames might have PTS values on them, and if these > differ from the predicted PTS, xine resets the buffers and jumps to the > new PTS value. xine lets the video PTS values dominate. Now, if the > Audio PTS values are correct, but the video PTS values are wrong, xine > will correct itself to the video, and this will result in xine thinking > the audio PTS values are wrong. > > Extract of running xine with "xine --verbose=3" > audio discontinuity #12, type is 2, disc_off 3904619 > waiting for in_discontinuity update #12 > fixing sound card drift by 1898 pts > video discontinuity #12, type is 2, disc_off 3904619 > fixing sound card drift by 1425 pts > audio discontinuity #13, type is 2, disc_off 4768619 > waiting for in_discontinuity update #13 > video discontinuity #13, type is 2, disc_off 4768619 > audio vpts adjusted to audio vpts > audio jump, diff=75600 > > So, xine is seeing jumps in audio and video pts values. > > Another possible reason for the problems, could be that the audio and > video are not multiplexed close enough together, so even with xine's > large buffers, it cannot fit the audio and video with the same PTS in > the buffer. > > You need to redo the PTS values in the stream so that xine does not see > any discontinuities. > </quote> > > What are PTS values? What do I need to read? I googled, but got a huge > number of replies and very little seemed to have much to do with it. If you > haven't any additional words it's hard to sort wheat from chaff ;-)
The presentation times stamps are generated by mplex. Its the job of mplex to multiplex audio and video closely together and generate appropriate decode (DTS) and presentation (PTS) time stamps. I doubt that mplex is generating wrong PTS values, but it is possible that you have found a situation where the audio and video are not closely (close in terms of sectors not time) multiplexed. Andrew could clarify that, but it seems he does not frequent this list these days. Selva ------------------------------------------------------- SF.Net email is sponsored by Shop4tech.com-Lowest price on Blank Media 100pk Sonic DVD-R 4x for only $29 -100pk Sonic DVD+R for only $33 Save 50% off Retail on Ink & Toner - Free Shipping and Free Gift. http://www.shop4tech.com/z/Inkjet_Cartridges/9_108_r285 _______________________________________________ Mjpeg-users mailing list [EMAIL PROTECTED] https://lists.sourceforge.net/lists/listinfo/mjpeg-users
