{
	Erik Reinhard's simple global tone-operator
}
{ Lwht = 1e10;		{ set on command line } }
{ Lavg = .5;		{ set on command line } }
{ a : 0.18;		{ set on command line } }
Lwhite : a/Lavg*Lwht;
L = a/Lavg*li(1);
sq(x) : x*x;
Ld = L*(1+L/sq(Lwhite))/(1+L);
mult = Ld/li(1);
ro = ri(1)*mult;
go = gi(1)*mult;
bo = bi(1)*mult;