As far as I know the below information is correct, but I didn't re-check everything.
you've got 3 possibilities to set the brightness settings (and other settings as well), all of them require a movie to be playing.
- right-click on the movie, options, filters, <video filter name (divx, xvid, ffdshow...>. This pops up the configuration window of the video filter. The filter probably has some options to set brightness. This is a system-wide setting.
- right-click on the movie, video, color controls.
This sets the hardware brightness and color controls on the overlay. This is also a system-wide setting, if I remember correctly. - go to preferences, video. You can choose settings for divx3, divx4+, ffdshow. (although I remember it was not completely efficient some time ago for divx4+, can't tell if this has changed since this post ). These settings are only for use in bsplayer (and stored in bsplayer's config file), not system-wide.