[mythtv-users] mythtranscode "memory leak" with ffmpeg on HDTV streams

[Jonathan Wang]

I'm experiencing what looks like a memory leak in mythtranscode when 
exporting HDTV streams to ffmpeg over a FIFO. I suspect that this is an 
instance of the problem documented here:

http://mythtv.org/pipermail/mythtv-users/2003-October/016426.html

where mythtranscode keeps buffering the recorded stream to the FIFO but 
ffmpeg doesn't pull the data off.

The actual symptom is that the resident and virtual space used by 
mythtranscode keeps growing by about 1M/sec - which, incidentally, is 
about the bitrate of the HD stream. The stream is transcoded until 
eventually mythtranscode fills up memory & swap and causes the 
system to thrash continually on iowait and get nothing done.

The command I'm using to do the transcode is:
/usr/bin/nuvexport --chanid=1006 --start=20060511233200 --mode=iPod 
--nice=19 --cutlist --nodenoise --nodeinterlace --nomultipass

which results in this call to mythtranscode:
/usr/bin/mythtranscode --showprogress -p autodetect -c 1006 -s 
2006-05-11-23-32-00 -f /tmp/fifodir_21618/ --honorcutlist

and this call to ffmpeg:
ffmpeg -y -f s16le -ar 48000 -ac 2 -i /tmp/fifodir_21618/audout -f 
rawvideo -pix_fmt yuv420p -s 1920x1080 -aspect 1.77777777777778 -r 
29.970 -i /tmp/fifodir_21618/vidout -aspect 1.3333 -r 29.97 -croptop 22 
-cropright 38 -cropbottom 22 -cropleft 38 -padtop 30 -padbottom 30 -s 
320x180 -b 384 -vcodec xvid -acodec aac -ab 96 -f mp4 -title Late Night 
With Conan O'Brien - Untitled 
/myth-data/ipodfeed/1006_20060511233200.ipod.mp4

Thanks,
Jonathan