[mythtv] Will the wife like it?

Bruce Markey mythtv-dev@snowman.net
Fri, 20 Dec 2002 14:53:51 -0800


Isaac Richards wrote:
> On Friday 20 December 2002 10:39 am, Rob Chambers wrote:
> 
>>After several days of tweaking and switching hardware around I have finally
>>ended up with a solution that has very acceptable quality although it is
>>not as good as the best recording level on Tivo.
> 
> 
> The best recording level on Tivo is something like 544x480 at pver 7000kbps, 
> IIRC.   If you set this stuff to 640x480 (ie, 18% more data) mpeg4 with a 
> target bitrate of 6600kbps and set the qmin variable to 4 or 5, I'm fairly 
> certain you'll end up with something mostly indistinguishable from the raw 
> input.  It'll use slightly more CPU than with the default bitrate and minimum 
> quality values, but I've still got plenty of CPU free with my XP 1800+.

Just for fun, in testing I've tried 720x480 which seems to
be the max my cards will support. It's even a little crisper
but, of course, there is the law of diminishing returns.
Unless, you plug a DVD player or digital cable box into an
S-video input you may not notice any real difference at
the higher resolution.

I've used a DVD player to play "Video Essentials" through
MythTV and I'm satisfied that the tuner card does a very
good job of sampling the input signal. However, broadcast
NTSC is inherently crappy. Pushing the limits to perfectly
reproduce a crappy signal mostly seems to just waste
resources. I believe that for most cases the myth defaults
are a reasonable tradeoff of quality for disk space.

I think the bigger question for comparing the image quality
with commercial products is the quality of TV-out.

--  bjm