[MEncoder-users] Best scaler?

[Pepe]

Hi. I've just found this list. 

I'd like to ask... what's the best way to scale (down) an image?

I just use the filter scale. According to the manual, that use a 
bicubic scaler. But there are some more which can be used through the -sws 
option. Which is the best?

I'm asking this because some time ago had some problems with a video. It was 
mainly dark, most of it very dark scenes. In the original there were some 
black areas, near there were dark areas (maybe dark red). The video generated 
by mencoder turned that dark areas into black, so a great quantity of detail 
was lost, it was really horrible. At first I thought it could be because of a 
low bitrate, but then I realize it was because of the scale filter, if I 
didn't use it, image improved a lot.

The original video was at 624x352, I was trying to reduced to 512x288.

I tried different values for -sws, but I got the same result. 

So what's the best way to scale down a video, specially if the image is very 
dark?

Sorry for my English.

-- 
pepe