[MPlayer-users] gamma control with -vo gl

[Vladimir Mosgalin]

Hello everybody.

How can I tweak gamma at playback? Well, "before the start" will work
fine for me, too. There is -vf eq2 which works, if I set in input.conf
F10 gamma -1
F11 gamma abs 1
F12 gamma +1

then pressing F10-F12 will change gamma during playback just fine. But,
it's said to be "very slow" in manpage - I can't say I feel that it's
that slow, but nevertheless. -vo gl claims to support gamma control with
yuv=3/yuv=4 modes, but it just doesn't work right. When using yuv=3 or 4
mode, F10-F12 keys work and bar that shows tweaking appears in osd, but
gamma control itself works wrong - when I reduce gamma, it's just only
gamma reduced, but image also becomes greener (quite noticeable), and
when I increase gamma, image becomes redder. Am I doing anything wrong?
Manpage claims per-channel gamma control for yuv=3/4 but I don't even
need that, changing gamma for all channels will do for me.

-- 

Vladimir