[mythtv] MPEG-4 trouble on SMP

Samit Basu mythtv-dev@snowman.net
Wed, 30 Oct 2002 22:35:50 -0500

Hi -

I've got a strange problem with mythtv when I use MPEG-4 encoding.
work fine, as do playbacks, but when I watch live TV, the video is
corrupted.  It looks
mostly fine, but there are blocking artifacts -- blocks of color, white and
black that
fade in and out periodically.  I don't have the same problem with rtjpeg,
and the problem
doesn't go away with reduced capture resolution (I tried down to 320 x 200).
I'm running
on a dual 1GHz PIII, and the artifacts go away when I run a non-SMP kernel.
the subject line)...  I looked at the rwlocks in RingBuffer.cpp, but wasn't
enough with the code to spot the problem (e.g., why is a read-lock used in
the Write
method?).  Any ideas?

Thanks in advance,

PS - Awesome PVR app!