Hello again.

I've done a little more digging, and think I've identified the problem now.  I 
wrote this rest of this email for the mjpeg-developer list to report as a bug 
while I was waiting for my previous message to be approved.  I am now 
registered to both lists, and am posting this email to -dev, where it belongs.  
I apologize for all the confusion.

-------------------
Greetings.

I think I've discovered a bug in mplex when multiplexing very low bitrate MPEG1 
VBR.  I have tried several GOP structures IPPPPP and IPP, the problem is that 
mplex does not "see" all the P frames and the resulting video plays too fast 
(presumably the PTS/DTS are calculated wrong)

Here is an excerpt from an mplex of an IPP stream:
   INFO: [mplex] No. Pictures    :    17982
   INFO: [mplex] No. Groups      :     8992
   INFO: [mplex] No. I Frames    :     8992 avg. size  1700 bytes
   INFO: [mplex] No. P Frames    :     8991 avg. size   198 bytes
   INFO: [mplex] No. B Frames    :        0 avg. size     0 bytes

there should be twice as many P frames as are reported.  This .m1v video file 
(352x240 29.97fps GOP=3 IPP) is encoded from a source which only changes every 
three frames, averages about 150Kbps, and has I frames that are less than 1 
packet for DVD mux. It plays just fine in quite a number of places, and is 
multiplexed correctly by the TMPGenc DVD Author app under Windows.

Anyway, check out the file if you can (a 256KB dd'd cut, encoded under Windows 
by latest
TMPGenc+ 2.5) http://asterisk.appliedtns.com/mpeg/timecode.m1v

Thanks!



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