[MEncoder-users] VHS rip with too dark scenes

[Munzuk]

Good night

Recently I found a movie ripped from vhs, the quality is poor and I'm trying 
to get it some better.

The main problem is that some scenes are too dark, barely a black screen, 
already tried to modify brightness and contrast with very bad results, so:

Is there any way to detect those scenes and improve at least a bit the 
illumination?

Thanks in advance.