[ATrpms-users] MythTV Transcode/Export Issues

[Kirk Bocek]

On 1/13/2011 6:50 AM, John Welch wrote:
> This might be a question better suited for the MythTV lists, but I
> figured I would start here where others are likely using the same
> software / versions as I am.
> 
> My MythTV back-end system is running under Fedora 14, with all myth
> and related (mplayer, ffmpeg, etc.) packages from the ATrpms repo.
> Ever since I've been running MythTV (0.18 days) I've always used
> 'nuvexport' to take certain recordings (usually TV series), cut the
> commercials out of them, and transcode to a different format (usually
> avi) to save disk space.  Due to issues with the way ffmpeg interacts
> with nuvexport I've flip-flopped between using ffmpeg and mencoder,
> but one way or another I've always been able to accomplish this task.
> Typically for an hour-long HD recording that starts out being around
> 6-7 GB I end up with a transcoded file around 300-400 MB.
> 
> Lately I've been having issues with this process.  It started with the
> last ffmpeg update.  The 'nuvexport' script / program apparently
> doesn't like the info being returned by 'ffmpeg --version'.  I've
> previously posted here about this issue.  Not really a big deal though
> because I've always been able to fall back to using mencoder.  Now
> however when I run 'nuvexport --mencoder' the process runs for a
> while, but usually when it gets to around 10% complete the process
> dies and I see a "core dumped" message related to the mencoder
> command.  I've also tried the "mythnuv2mkv" script, which I've
> previously had some success with, but this uses mencoder as well for
> the transcoding and I get similar results -- core dump after running
> for some time.
> 
> So, basically I guess I have a few questions:
> 
> 1) Is anyone else having this problem?  I'm kind of thinking there
> might be some issue with my system, as I've been searching around and
> not finding anyone reporting this or similar problems.  I've got other
> systems around, but have never had any luck working with the MythTV
> recordings anywhere other than the back-end server.
> 
> 2) Probably a question specifically for Axel and the other repo
> maintainers, but would it be possible to get updated mplayer and
> ffmpeg packages?  I'm sure there is some significance to them, like
> they contain important fixes or milestones, but to me the current
> packages seem to be fairly random snapshots (snapshot from 2010-10-02
> for mplayer and git repo from 2010-10-24 for ffmpeg)
> 
> 3) Does anyone have any scripts, command lines, programs, etc. that
> can be used to accomplish the same thing that 'nuvexport', and
> 'mythnuv2mkv.sh' are doing, namely get rid of commercials and reduce
> size?

Nuvexport stopped working for me maybe 2 or 3 years ago. I went to the
mythtv-users list several times over that period seeing if there was a fix but
I haven't had any success. Try googling "nuvexport
site:http://mythtv.org/pipermail/mythtv-users/" to see all the woe and suffering.

The story I get is that ffmpeg has so dramatically changed their command line
options from version to version that the nuvexport people have had trouble
keeping up.

The issue I seem to be having now is with the x264 files created by my HDPVR.
These seem to be difficult to edit with *any* tool. I've tried using ffmpeg to
do something simple like trim a little bit off the beginning and ending of a
recording. No luck. It doesn't help that I can't seem to find any tools for
Windows that can reliably edit large x264 files that contain 5.1 audio.

If you find any answers, please share them.

Kirk Bocek