[mythtv-users] cut HD-PVR content with audio/video sync issues

[Doug Vaughan]

I have not tried Robert's script in a very, very long time. The only 
reason is that I do not trust the automated process to decide where the 
cuts should be and you cannot adjust the edits in a Avidemux project 
file at least with v2.4.x this may have changed in v2.5.x.

As for Avidemux v2.5.x, just last week I tried Ubuntu's v2.5.1 deb, a 
v2.5.2 deb and compiled 2.5.2 version from the Avidemux svn. All aborted 
trying to open a HDPVR mpg/AC3 recording. I posted the abort on the 
Avidemux forum but did not get a response. I would like to upgrade but 
right now I am sticking to my compiled version from late last November.

I used to sometimes get audio out of sync. If the out of sync was 
consistent throughout the file I used mkvmerge GUI to make adjustments. 
Out of sync audio that happened somewhere after the beginning of the 
loss-less video was usually a reflection of some transmission error 
recorded on the original HDPVR mpg file.

When I first got my HDPVR I could not channel change my STB so I 
recorded on a STB/PVR before using the HDPVR. Every time I had an HDPVR 
recoding issue I could trace it back to the source. One movie I recorded 
multiple times from my Cable company and it always had the same picture 
and sound errors in the same time locations.

Over the last 12 months or so there has been both firm ware upgrades but 
also a number of improvements on the Linux side (driver and MythTV). So 
I rarely see audio out of sync any more.

I may give Roberts script another shot and adjust the commercial cuts 
within MythTV itself. I just had gotten very used to the manual process.

I thought I read that your audio goes out of sync gradually. If true 
then try an experiment.
1) Use the script's avidemux project file but change the output 
container to be avi rather than mkv
2) Then process the resulting avi file through ffmpeg or mkvmerge to see 
if the final mkv file maintains audio sync.