[MEncoder-users] Please help: Scale, expand and aspect

[Magnus Karlsson]

Hi,

I've been struggling with mencoder for a while now, but I do not still 
get the scale and aspects.

I simply want to rip my DVD:s to DivX movies with correct aspect. 
However I get egg-headed people all the time on a 4:3 fullscreen movie.

Now, 99% of my source formats are 16:9 or 4:3 PAL movies, the output 
should be 16:9 or 4:3 PAL movies. Should I not keep the original size?

In the documentation 
(http://www.mplayerhq.hu/DOCS/HTML/en/menc-feat-vcd-dvd.html#menc-feat-vcd-dvd-output-aspect) 
I've found the following that actually works:

"-vf scale="720:432,expand=720:576 -lavcopts aspect=16/9" with the explanation:
"To calculate the correct scaling size, use the expanded PAL width of 1024/2.35 = 432",
	but why? Where does these values come from?

Please help me out to calculate the scale and expand values.

Regards,
Magnus