public override Double Get(Double x, Double y)
{
var value = this.Source.Get(x, y);
// Apply brightness
value += this.Brightness.Get(x, y);
// Subtract contrastThreshold, scale by contrastFactor, add contrastThreshold
var threshold = this.ContrastThreshold.Get(x, y);
value -= threshold;
value *= this.ContrastFactor.Get(x, y);
value += threshold;
return value;
}