[mythtv] MythArchive bugs and "fixes"

Martin van Es mrvanes at gmail.com
Wed Oct 22 19:47:33 UTC 2008


I'm using MythTV together with an hauppauge pvr-500 and recently
upgraded to 0.21-fixes (svn).
First of all I'd like to congratulate you all on the achievements in
this "release". Silent tuner failover when watching live-tv is a
blessing, fill zoom for watching movies (using Internal player instead
of mplayer) is sweet!

After upgrading I thought I'd give MythArchive a try but it failed. It
turns out several things are broken (for me) and following are the
fixes needed to make things work:

1. mythreplex fails because the audio stream was not correctly
detected by mythburn.py. After some debugging it turns out that
mytharchivehelper writes lower-case types in the streaminfo.xml, but
mythburner.py strictly looks for AC3 and MP2 (capitals). As a result,
no valid audio stream is found and the demux fails. Changing all
capital references to lowercase ones in mythburner.py fixed this

2. After getting mythreplex to start without failure, it runs endless
(or so it seems). It turns out it tries to append an extra frame in
the audio stream so often that the mythburner.log file quickly became
larger than the movie it was trying to demux. After some googling I
found m2psd, which is tailor made to demux pvr-150/250/350 mpeg2
streams. Perfect for the job, I thought.
I created a little wrapper script that generates the demuxed streams
and renames them so that mythburner.py can find them afterwards:

/usr/bin/m2psd -a $MPG2FILE $BASENAME
# Rename files for further mytharchive processing
mv ${BASENAME}-0.mpa ${BASENAME}0.mp2
mv ${BASENAME}-0.mpv ${BASENAME}.mv2

3. In mythburner.py I changed deMultiplexMPEG2File() function to
generate the demux command like this:
command = "m2psd.sh %s %s" % (mediafile, folder + "/stream")

After these changes, I was able to sucessfully create a DVD iso from
several recordings. (4. Actually I missed mkisofs because debian wants
people to move on to genisoimage, but after installing the deprecated
mkisofs transition package which creates a symlink to genisoimage, all
went smooth and well).

I'm not saying these changes should make it into mytharchive, I just
wanted to give an impression of my experiences and solutions to the
problems I encountered.
Hope they may be of any help in understanding the problems a generic
pvr-500 user may (will?) experience using mytharchive in 0.21-fixes.

if but was of any use, it would be a logic operator

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