[Cin] Chromakey improvements checked in to GIT

[Andrea paz]

I tried to start CinGG (ffmpeg7) in wayland. During startup I get this error:
BC_DisplayInfo::gl_fb_config failed
Error I don't have in Xorg. However, everything works normally. I've
tried both X11 and X11-OpenGL driver, but I don't notice any
difference.
As a test I put in the chroma-key plugin and observed a strange
behavior: now the threshold works from the value 40 instead of a value
just above 0. Even going back into Xorg the same behavior remains. Why
did it work correctly for me the first time and from the second test
onwards the threshold seems to shift from 0 to 40? Anyway it is not
important, I will do more tests but it is probably due to some mistake
of mine.

Instead, an important thing that I had noticed even before trying
wayland, but forgot to report in the previous email is that the
“Default” button returns the threshold to 10, as required. In
contrast, the “Reset” button on the slider brings it back to 0. This
difference can also be seen in chromakey.C :

ChromaKeyConfig::ChromaKeyConfig()
{
       reset(RESET_DEFAULT_SETTINGS);
}

void ChromaKeyConfig::reset(int clear)

{
    switch(clear) {
        case RESET_ALL :
            red = 0.0;
            green = 0.0;
            blue = 0.0;
            threshold = 0.0;
            use_value = 0;
            slope = 0.0;
            break;
        case RESET_RGB :
            red = 0.0;
            green = 0.0;
            blue = 0.0;
            break;
        case RESET_SLOPE :
            slope = 0.0;
            break;
        case RESET_THRESHOLD :
            threshold = 0.0;
            break;
        case RESET_DEFAULT_SETTINGS :
        default:
            red = 0.0;
            green = 0.0;
            blue = 0.0;
            threshold = 10.0;
            use_value = 0;
            slope = 0.0;
            break;
    }
}

I think in each line that threshold appears the value should be raised to 10.0.