%ffp

ctl(0):"Saturate R",size=(*,6),pos=(225,42),fontcolor=black,Range=(-200,300),val=100
ctl(1):"Saturate G",size=(*,6),pos=(225,52),fontcolor=black,Range=(-200,300),val=100
ctl(2):"Saturate B",size=(*,6),pos=(225,62),fontcolor=black,Range=(-200,300),val=100



ForEveryTile:{

			int r,g,b,Gray;

			for (y=y_start; y<y_end; y++){
				if(updateProgress(y,y_end)) abort();
			for (x=x_start; x<x_end; x++){

				r=src(x,y,0);g=src(x,y,1);b=src(x,y,2);
				
				Gray=(r+g+b)/3;
				
				pset(x,y,0, ((100-ctl(0))*Gray + ctl(0)*r)/100 );
				pset(x,y,1, ((100-ctl(1))*Gray + ctl(1)*g)/100 );
				pset(x,y,2, ((100-ctl(2))*Gray + ctl(2)*b)/100 );


			}}

	return true;
}