Convert Flicker.cg to glsl problem

Hi,

I wish to convert Sony PVM S-video from Analog shader Pack V3 into glsl format.

I have just one problem with flicker.glsl, in the menu parameter the “Interlacing Scanline Bright %” option was not present.

I copy/paste this option from cg shader ( flicker.cg ), now I have the option in Menu parameter but is still inactive, I don’t understand.

If someone have an idea,

Thanks and sorry for my bad English