// Метод Оцу
public int MethodOtsu(int index)
{
if (index < 0 || index > PixelMapList.Count || PixelMapList.Count == 0)
{
return(-1);
}
int height = 0;
int width = 0;
Bitmap newmap = CreateNewMapForMap(index, ref height, ref width);
if (newmap == null)
{
return(-1);
}
int[] p = new int[256]; // ?
double[] pp = new double[256]; //?
int total = 0;
int r = 0, g = 0, b = 0, res = 0;
for (int I = 0; I < p.Length; I++)
{
p[I] = 0;
}
for (int I = 0; I < newmap.Width; I++)
{
for (int J = 0; J < newmap.Height; J++)
{
GetRGB(newmap, I, J, ref r, ref g, ref b);
res = Convert.ToInt32(RedApproximation * r + GreenApproximation * g + BlueApproximation * b);
p[res]++;
}
}
for (int I = 0; I < 256; I++)
{
total += p[I];
}
for (int I = 0; I < 256; I++)
{
pp[I] = Convert.ToDouble(p[I]) / Convert.ToDouble(total);
}
int t = 0;
double q1, q2, m1, m2, s1, s2, sw = Double.MaxValue; //?
for (int I = 0; I < 256; I++)
{
q1 = q2 = 0;
m1 = m2 = 0;
s1 = s2 = 0;
for (int J = 0; J <= I; J++)
{
q1 += pp[J];
}
for (int J = I + 1; J < 256; J++)
{
q2 += pp[J];
}
for (int J = 0; J <= I; J++)
{
m1 += J * pp[J] / q1;
}
for (int J = I + 1; J < 256; J++)
{
m2 += J * pp[J] / q2;
}
for (int J = 0; J <= I; J++)
{
s1 += Math.Pow((J - m1), 2) * pp[J] / q1;
}
for (int J = I + 1; J < 256; J++)
{
s2 += Math.Pow((J - m2), 2) * pp[J] / q2;
}
if ((q1 * s1 + q2 * s2) < sw)
{
sw = q1 * s1 + q2 * s2;
t = I;
}
}
for (int I = 0; I < newmap.Width; I++)
{
for (int J = 0; J < newmap.Height; J++)
{
GetRGB(newmap, I, J, ref r, ref g, ref b);
res = Convert.ToInt32(RedApproximation * r + GreenApproximation * g + BlueApproximation * b);
if (res > t)
{
newmap.SetPixel(I, J, Color.FromArgb(0, 0, 0));
}
else
{
newmap.SetPixel(I, J, Color.FromArgb(255, 255, 255));
}
}
}
PixelMapList.Add(newmap);
return(0);
}
