[mythtv-users] nuvexportrc default changes

Chris Petersen lists at forevermore.net
Tue May 29 00:37:30 UTC 2007


Christopher Friend wrote:
> crop_pct has changed from 2 to 1.5. I would assume someone's noticed too 
> much actual footage being chopped off by the 2 value, always seemed ok to me 
> though...

Happened when I got digital cable and started looking closely at the
signal.  It honestly doesn't make much difference at low res because of
the rounding-up needed to meet mpeg standards (8px chunks).

> Xvid's v_bitrate changed from 960 to 768 . I'm thinking this may have 
> something to do with the next bit...

due to res.

> Xvid's default width is now 512 instead of 624. Looks like someone decided 
> to make Xvid files more the realm of very portable media, small resolution 
> to play on pmp's or the web, with a small file size to reflect the small res 
> and give the thing a much smaller file size. Either that or there's a good 
> reason for using 512 (ie. wider compatibility).

Actually, it has to do with the resolution of the video sent out by the
satellite/cable companies.  All of the SD recordings coming over digital
(satellite or cable) appear to be 328x480, 528x480 or 544x480 (all
interlaced).  If your analog tuners are stretching it to 720x480,
there's still no point in encoding it at a larger resolution than the
original digital image.

The 768kbps change reflects an approximate percentile change to go along
with the smaller resolution, keeping the average bytes-per-pixel about
the same.

Anywaym, that's why they're all overridable.  I use the --profile stuff
extensively now, and encode shows at different resolutions based on the
res they come in from comcast (and I use a container like mp4, which
unlike avi is capable non-square pixels and anamorphic display).

> And one more thing... how do I get new versions of nuvexport now it's been 
> added to mythtv's svn? (after xris stops handing out tar.gz's, obviously).

No worries, I'll probably always have tarballs/packages on my site (or
mythtv.org after .21 is released).

-Chris

-------------- next part --------------
A non-text attachment was scrubbed...
Name: signature.asc
Type: application/pgp-signature
Size: 189 bytes
Desc: OpenPGP digital signature
Url : http://mythtv.org/pipermail/mythtv-users/attachments/20070528/226e588f/attachment.pgp 


More information about the mythtv-users mailing list