[mythtv] transcoding with cutlist

Geoffrey Hausheer ou401cru02 at sneakemail.com
Wed Aug 13 21:35:38 EDT 2003


On 13 Aug 2003 18:45:56 +0200, "Martin Moeller martin-at-martinm-76.dk
|mythtv/1.0-Allow|" <mvx1hgfxer0t at sneakemail.com> said:
> 
> > If anyone knows any clever ways to make mplayer work with named-pipes,
> > I'd be glad to hear them.
> I thought I did but it seems I don't.. :-/

Well, after much playing, I have learned some things: mencoder works fine
with a single named pipe.  However, when reading from two sources (using
-audiofile) it doesn't necessarily read at the same speed from both
streams.  Since fifos are blocking, eventually you will block on writing
one stream while mencoder blocks on reaidng the other, and you are
deadlocked.  I have played with creating a cache to aleviate this
problem, but it onlys works for a while.  Eventually the same thing will
happen.

The only solution seems to require a muxed stream, which sucks.  The most
likely option would be to have mythtranscode build a Quicktime container
and drop the raw audio/video data into it (it is the only container
format I've seen which supports raw data).  The downside is (a) it is a
pain to implement, and (b) apparently mencoder has problems reading that
specific file format (at least from my searching on their lists).  The
next option would be to build a new demuxer for mencoder which supports
raw data, but that leaves us in a similar state as we are now (need an
mencoder patch to read the files).  The upside would be that we could do
commercial processing with very little loss, but it would still require
some sort of audio-sync to be done in mythtranscode.

So basically, I see no easy solution, and I've exhausted all of my ideas.
I'll now stop banging my head against the wall, unless someone has some
other ideas.

.Geoff


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