[MEncoder-users] frame size confusion

[Dave M G]

Mencoder list,

Thank you to everyone who has responded and I'm sorry because I feel I 
have been unfocused in resolving this issue.

I've read more on the link provided and experimented with some different 
settings, and I hope I understand my situation better.

I think when I asked about saving in 720x406, I was not approaching the 
problem correctly. I think I was not taking into account the difference 
between square pixels and anamorphic pixels.

For saving my 720x480 images as AVI files, I shouldn't be converting the 
pixel size, I should instead preserve the aspect ration. Is that correct?

If so, then what exactly is the command to do so? I looked on the 
Mencoder documentation and found this:
http://www.mplayerhq.hu/DOCS/HTML/en/aspect.html

But I'm unsure as to how to apply that in the command I have running.

The example they give is:
mencoder sample-svcd.mpg -vf crop=714:548:0:14 -oac copy -ovc lavc \ 
-lavcopts vcodec=mpeg4:mbd=2:trell:autoaspect -o output.avi

And my command is:
mencoder input.mpg -ovc lavc -lavcopts 
vcodec=mpeg4:vbitrate=1100:vhq:vqmin=2:vlelim=-4:vcelim=9:lumi_mask=0.05:dark_mask=0.01 
-vf scale=720:406,pp=lb -oac mp3lame -lameopts preset=standard -o output.avi

So I tried combining them, and putting the pixel scale to 720x480, like so:
vcodec=mpeg4:vbitrate=1100:vhq:vqmin=2:vlelim=-4:vcelim=9:lumi_mask=0.05:dark_mask=0.01:mbd=2:trell:autoaspect 
-vf scale=720:480,pp=lb -oac mp3lame -lameopts preset=standard -o output.avi

But then I got a weird result. The image came back as 854x480 pixels, 
and it seems to have a fair amount of jpeg compression artifacts. I'm 
not sure if the compression artifacts are just more noticeable at a 
larger size, or if I've somehow hosed my quality settings.

Or maybe I'm just doing everything completely wrong here.

Can someone straighten me out here?

Thank you for any advice.

-- 
Dave M G