public Bitmap FloydSteinberg()
{
RGBint oldPixel, qErr = new RGBint(); Color newPixel;
RGBint[,] arr = new RGBint[bmp.Height, bmp.Width];
for (int i = 0; i < bmp.Height; i++)
{
for (int j = 0; j < bmp.Width; j++)
{
arr[i, j] = new RGBint(bmp.GetPixel(j, i).R, bmp.GetPixel(j, i).G, bmp.GetPixel(j, i).B);
}
}
for (int i = 0; i < bmp.Height; i++)
{
for (int j = 0; j < bmp.Width; j++)
{
oldPixel = arr[i, j];
newPixel = FindColorFromPal((int)oldPixel.Rint, (int)oldPixel.Gint, (int)oldPixel.Bint);
bmp.SetPixel(j, i, newPixel);
qErr.Set(oldPixel.Rint - newPixel.R, oldPixel.Gint - newPixel.G, oldPixel.Bint - newPixel.B);
if (j < bmp.Width - 1)
{
arr[i, j + 1].Set(arr[i, j + 1].Rint + qErr.Rint * 7 / 16, arr[i, j + 1].Gint + qErr.Gint * 7 / 16, arr[i, j + 1].Bint + qErr.Bint * 7 / 16);
if (i < bmp.Height - 1)
{
arr[i + 1, j + 1].Set(arr[i + 1, j + 1].Rint + qErr.Rint * 1 / 16, arr[i + 1, j + 1].Gint + qErr.Gint * 1 / 16, arr[i + 1, j + 1].Bint + qErr.Bint * 1 / 16);
}
}
if (i < bmp.Height - 1)
{
arr[i + 1, j].Set(arr[i + 1, j].Rint + qErr.Rint * 5 / 16, arr[i + 1, j].Gint + qErr.Gint * 5 / 16, arr[i + 1, j].Bint + qErr.Bint * 5 / 16);
if (j > 0)
{
arr[i + 1, j - 1].Set(arr[i + 1, j - 1].Rint + qErr.Rint * 3 / 16, arr[i + 1, j - 1].Gint + qErr.Gint * 3 / 16, arr[i + 1, j - 1].Bint + qErr.Bint * 3 / 16);
}
}
}
}
return(bmp);
}
public Bitmap FloydSteinberg()
{
RGBint old = new RGBint(), qErr = new RGBint();
Color c;
//Locks the bitmap bits
Rectangle rect = new Rectangle(new Point(0, 0), bmp.Size);
BitmapData bmpData = bmp.LockBits(rect, ImageLockMode.ReadWrite, bmp.PixelFormat);
//Adress of the first line.
IntPtr ptr = bmpData.Scan0;
//Declare array to hold the values.
int bpp = Bitmap.GetPixelFormatSize(bmp.PixelFormat) / 8;
int bmpWidth = bmp.Width, bmpHeight = bmp.Height;
int stride = Math.Abs(bmpData.Stride);
int bytes = stride * bmp.Height;
byte[] rgbValues = new byte[bytes];
//Copy values to array.
Marshal.Copy(ptr, rgbValues, 0, bytes);
//Create copy with float type.
double[] rgbValuesFloat = Array.ConvertAll <byte, double>(rgbValues, new Converter <byte, double>(ByteToDouble));
for (int i = 0; i < bmp.Height; i++)
{
for (int j = 0; j < Math.Ceiling((double)stride / bpp); j++)
{
if (j < bmpWidth)
{
int currentRowCol = i * stride + j * bpp;
old.Set(rgbValuesFloat[currentRowCol + 2], rgbValuesFloat[currentRowCol + 1], rgbValuesFloat[currentRowCol]);
c = FindColorFromPal((int)old.Rint, (int)old.Gint, (int)old.Bint);
//Set new pixel value.
rgbValuesFloat[currentRowCol + 2] = c.R; rgbValuesFloat[currentRowCol + 1] = c.G; rgbValuesFloat[currentRowCol] = c.B;
qErr.Set(old.Rint - c.R, old.Gint - c.G, old.Bint - c.B);
if (j < bmpWidth - 1)
{
rgbValuesFloat[currentRowCol + bpp + 2] = rgbValuesFloat[currentRowCol + bpp + 2] + qErr.Rint * 7 / 16;
rgbValuesFloat[currentRowCol + bpp + 1] = rgbValuesFloat[currentRowCol + bpp + 1] + qErr.Gint * 7 / 16;
rgbValuesFloat[currentRowCol + bpp] = rgbValuesFloat[currentRowCol + bpp] + qErr.Bint * 7 / 16;
if (i < bmpHeight - 1)
{
rgbValuesFloat[currentRowCol + stride + bpp + 2] = rgbValuesFloat[currentRowCol + stride + bpp + 2] + qErr.Rint * 1 / 16;
rgbValuesFloat[currentRowCol + stride + bpp + 1] = rgbValuesFloat[currentRowCol + stride + bpp + 1] + qErr.Gint * 1 / 16;
rgbValuesFloat[currentRowCol + stride + bpp] = rgbValuesFloat[currentRowCol + stride + bpp] + qErr.Bint * 1 / 16;
}
}
if (i < bmpHeight - 1)
{
rgbValuesFloat[currentRowCol + stride + 2] = rgbValuesFloat[currentRowCol + stride + 2] + qErr.Rint * 5 / 16;
rgbValuesFloat[currentRowCol + stride + 1] = rgbValuesFloat[currentRowCol + stride + 1] + qErr.Gint * 5 / 16;
rgbValuesFloat[currentRowCol + stride] = rgbValuesFloat[currentRowCol + stride] + qErr.Bint * 5 / 16;
if (j > 0)
{
rgbValuesFloat[currentRowCol + stride - bpp + 2] = rgbValuesFloat[currentRowCol + stride - bpp + 2] + qErr.Rint * 3 / 16;
rgbValuesFloat[currentRowCol + stride - bpp + 1] = rgbValuesFloat[currentRowCol + stride - bpp + 1] + qErr.Gint * 3 / 16;
rgbValuesFloat[currentRowCol + stride - bpp] = rgbValuesFloat[currentRowCol + stride - bpp] + qErr.Bint * 3 / 16;
}
}
}
}
}
//Convert back.
rgbValues = Array.ConvertAll <double, byte>(rgbValuesFloat, new Converter <double, byte>(DoubleToByte));
//Copy them back.
Marshal.Copy(rgbValues, 0, ptr, bytes);
//Unlock the bits.
bmp.UnlockBits(bmpData);
return(bmp);
}
