[MEncoder-users] Can't get enough quality with xvid

[Pepe]

I've got a video from internet, it's an xvid with a very excelent image 
quality. Unfortunately I have to scale it a little bit so I can see it 
correctly in my dvd player.

The original video is about 1 hour and 20 minutes length, and its bitrate is 
1084 kbps, resolution is 704x528.

I re-encoded to scale to 704x576, but image in my video is worse, more 
"blocky". This is the command I used (this is the 2nd pass, the first one is 
the same with "pass=1:turbo"):

mencoder -noodml -o my_video.avi \
  -oac copy \
  -ovc xvid \
  -xvidencopts 
bitrate=1064:nointerlacing:nopacked:pass=2:max_iquant=31:max_pquant=31:max_bquant=31:max_bframes=0 
\
  -vf-add scale=704:576 -zoom \
  -vf-add harddup \
  -force-avi-aspect 4:3 \
  -sws 9  \
  orig_video.avi

I didn't use b-frames because my dvd player doesn't like them in hi-res 
videos.

Is there any other option I should use to improve quality?

-- 
Pepe