[Mplayer-dvb] DVB vertical resolutions

[Manuel Panea-Doblado]

Hi,

In file .../mplayer-xx/DOCS/DVB it is mentioned:

> Image size:
> ~~~~~~~~~~~
> DVB card allows only 2 vertical resolutions: 288 and 576.
> If your video height differs, you have to clip it or extend by adding
> black bands. It's done by mplayer, just specify image size using the
> -x and -y options. You must use either -y 288 or -y 576.

What does this exactly mean? I was hoping I could have an AVI file
with a resolution of, say, 720x288 and play it through the DVB card
and the picture would be expanded by the DVB card to 720x576, but this
is not so. I can have any resolution at all, for example 500x400, and
mplayer always adds black bands to make it 720x576 (even if I don't
use the -y option), but the picture itself stays 500x400.
Could you please clarify?

Another question: I want to convert VDR files to Divx. Unfortunately,
my computer is a bit too slow to play the Divx files generated without
special options. I'm playing around with different options trying to
get a compromise between replay speed and picture quality. If I tell
mencoder to rescale the movie down to about 600x480 and fps from 25
down to 18 or 20, then my computer can play them without framedrops or
stammering.  Could you perhaps do some recommendation about which
mencoder options are likely to produce faster replayable Divx files
while maintaining best possible quality?

Thanks,

-- 
  Manuel Panea                    Tel. +49 89 3299 1133
  Rechenzentrum Garching          Fax  +49 89 3299 1301
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