private static byte[] GetReducedBitmapKAverage(byte[] source, int width, int height, int k)
{
if (source == null)
{
throw new Exception("Source Bitmap is null");
}
if (k <= 0)
{
throw new Exception("K musi być większe od 0");
}
Color[] means = new Color[k];
double[,] nextMeans = new double[k, 5];
//array for calcualtio of next mean
//[k,0]=A of color, [k,1]=R of color, [k,2]=G of color, [k,3]=B of color,
//[k,4]=count of colors nearest to previous mean
RSTColorTree tree = new RSTColorTree();
for (int i = 0; i < k; i++)
{
means[i] = GetRandomColor();
}
bool changed = true;
int iterationCount = 0;
while (changed && iterationCount < 1e4) //if iteration bugger than 10000 stop
{
changed = false;
for (int i = 0; i < height; i++)
{
for (int j = 0; j < width; j++)
{
Color color = source.GetPixelFromByteArray(j, i, width);
double minDist = color.GetDistanceBeetweenColors(means[0]);
int minIndex = 0;
for (int c = 1; c < k; c++)
{
double dist = color.GetDistanceBeetweenColors(means[c]);
if (dist < minDist)
{
minDist = dist;
minIndex = c;
}
}
tree.Insert(color, means[minIndex]);
nextMeans[minIndex, 0] += color.A;
nextMeans[minIndex, 1] += color.R;
nextMeans[minIndex, 2] += color.G;
nextMeans[minIndex, 3] += color.B;
nextMeans[minIndex, 4]++; //increase number of colors
}
}
for (int index = 0; index < k; index++)
{
if (nextMeans[index, 4] > 0)
{
byte A = (byte)(nextMeans[index, 0] / nextMeans[index, 4]);
byte R = (byte)(nextMeans[index, 1] / nextMeans[index, 4]);
byte G = (byte)(nextMeans[index, 2] / nextMeans[index, 4]);
byte B = (byte)(nextMeans[index, 3] / nextMeans[index, 4]);
Color tmp = Color.FromArgb(A, R, G, B);
if (tmp != means[index])
{
means[index] = tmp;
changed = true;
}
}
}
iterationCount++;
}
for (int i = 0; i < height; i++)
{
for (int j = 0; j < width; j++)
{
Color c = source.GetPixelFromByteArray(j, i, width);
source.SetPixelInByteArray(j, i, width, tree.GetNewColor(c));//fill source with new colors
}
}
return(source);
}
private static byte[] GetReducedBitmapKPopular(byte[] source, int width, int height, int k)
{
if (source == null)
{
throw new Exception("Source Bitmap is null");
}
if (k <= 0)
{
throw new Exception("K musi być większe od 0");
}
RSTColorTree tree = new RSTColorTree();
Node[] popularColors = new Node[k];
for (int i = 0; i < height; i++)
{
for (int j = 0; j < width; j++)
{
Color color = source.GetPixelFromByteArray(j, i, width);
Node node = tree.Insert(color);
if (popularColors.FirstOrDefault(c => c == node) != null)
{
break;
}
for (int index = 0; index < k; index++)
{
if (popularColors[index] == null)
{
popularColors[index] = node;
break;
}
else if (popularColors[index].counter < node.counter)
{
for (int index2 = k - 1; index2 > index; index2--)
{
popularColors[index2] = popularColors[index2 - 1];
}
popularColors[index] = node;
break;
}
}
}
}
for (int i = 0; i < height; i++)
{
for (int j = 0; j < width; j++)
{
Color color = source.GetPixelFromByteArray(j, i, width);
double minDist = color.GetDistanceBeetweenColors(popularColors[0].Value);
int minIndex = 0;
for (int index = 0; index < k; index++)
{
if (popularColors[index] != null)
{
double dist = color.GetDistanceBeetweenColors(popularColors[index].Value);
if (dist < minDist)
{
minIndex = index;
minDist = dist;
}
}
}
source.SetPixelInByteArray(j, i, width, popularColors[minIndex].Value);
}
}
return(source);
}
