/// <summary>
/// Implements filter rebuilding.
/// </summary>
protected override void Rebuild()
{
float s = (Intensity.log05 / (float)Math.Log(0.5 - value2gamma(shadows)));
float l = (Intensity.log05 / (float)Math.Log(0.5 + value2gamma(lights)));
this.values = Intensity.LogStretch(s, l, 256);
}
/// <summary>
/// Returns the correction mask.
/// </summary>
/// <param name="s">Shadows</param>
/// <param name="l">Highlights</param>
/// <param name="length">Length</param>
/// <returns>Matrix</returns>
public static float[,] LogStretch(float s, float l, int length)
{
float[,] table = new float[length, length];
float w, v;
int x, y;
for (x = 0; x < length; x++)
{
w = x / (float)length;
for (y = 0; y < length; y++)
{
v = y / (float)length;
table[x, y] = Intensity.LogStretch(w, v, s, l);
}
}
return(table);
}