public static Tuple <Image, Image, Complex[, ]> CalculateFFT(Image source)
{
Bitmap resultAmplitude = new Bitmap(source);
Bitmap result = new Bitmap(source);
FasterBitmap fasterBitmapSrc = new FasterBitmap(source as Bitmap);
FasterBitmap fasterBitmapAmplitude = new FasterBitmap(resultAmplitude);
FasterBitmap fasterBitmapResult = new FasterBitmap(result);
fasterBitmapAmplitude.LockBits();
fasterBitmapSrc.LockBits();
fasterBitmapResult.LockBits();
Complex[,] original = new Complex[source.Width, source.Height];
for (int x = 0; x < source.Width; x++)
{
for (int y = 0; y < source.Height; y++)
{
original[x, y] = fasterBitmapSrc.GetPixel(x, y).R;
}
}
Complex[,] fourier = fft2(original);
fourier = ShiftComplex(fourier);
double[,] modulus = new double[fourier.GetLength(0), fourier.GetLength(1)];
for (int x = 0; x < fourier.GetLength(0); x++)
{
for (int y = 0; y < fourier.GetLength(1); y++)
{
modulus[x, y] = Modulus(fourier[x, y].Real, fourier[x, y].Imaginary);
}
}
double[,] amplitude = Normalize(modulus, source.Width, source.Height);
for (int x = 0; x < source.Width; x++)
{
for (int y = 0; y < source.Height; y++)
{
byte color = Convert.ToByte(amplitude[x, y]);
fasterBitmapAmplitude.SetPixel(x, y, Color.FromArgb(color, color, color));
}
}
Complex[,] fourierTAB = new Complex[fourier.GetLength(0), fourier.GetLength(1)];
fourierTAB = fourier;
fasterBitmapAmplitude.UnlockBits();
fasterBitmapSrc.UnlockBits();
fasterBitmapResult.UnlockBits();
return(new Tuple <Image, Image, Complex[, ]>(resultAmplitude, null, fourierTAB));
}
private Histogram(FasterBitmap bitmap, int channel = 0)
{
Values = new int[256];
for (int i = 0; i < bitmap.Width; i++)
{
for (int j = 0; j < bitmap.Height; j++)
{
var color = bitmap.GetSingleChannel(i, j, channel);
Values[color]++;
}
}
}
public static List <Histogram> CreateHistogram(Image image)
{
var result = new Bitmap(image);
var fasterBitmap = new FasterBitmap(result);
var list = new List <Histogram>();
fasterBitmap.LockBits();
if (Image.GetPixelFormatSize(image.PixelFormat) == 8)
{
list.Add(new Histogram(fasterBitmap, 0));
fasterBitmap.UnlockBits();
return(list);
}
list.Add(new Histogram(fasterBitmap, 0));
list.Add(new Histogram(fasterBitmap, 1));
list.Add(new Histogram(fasterBitmap, 2));
fasterBitmap.UnlockBits();
return(list);
}
public static Tuple <Image, Image> ApplyFilter(Image source, Complex[,] fourierTAB, int filtr, int radius, int radius2, int K, int L, double angle, double phiOffset)
{
Bitmap result = new Bitmap(source);
Bitmap resultMask = new Bitmap(source);
FasterBitmap fasterBitmapResult = new FasterBitmap(result);
FasterBitmap fasterBitmapMask = new FasterBitmap(resultMask);
fasterBitmapResult.LockBits();
fasterBitmapMask.LockBits();
double[,] modulus = new double[fourierTAB.GetLength(0), fourierTAB.GetLength(1)];
switch (filtr)
{
case 0:
fourierTAB = LowpassFilter(fourierTAB, radius);
break;
case 1: fourierTAB = HighpassFilter(fourierTAB, radius); break;
case 2: fourierTAB = BandWithFilter(fourierTAB, radius, radius2); break;
case 3: fourierTAB = BandPassFilter(fourierTAB, radius, radius2); break;
case 4: fourierTAB = EdgeDetection.createEdgeDetectionFilter(fourierTAB, fourierTAB.GetLength(0), fourierTAB.GetLength(1), angle, phiOffset, radius); break;
case 5: fourierTAB = ModifyFourierPnm(fourierTAB, K, L); break;
}
//
for (int x = 0; x < fourierTAB.GetLength(0); x++)
{
for (int y = 0; y < fourierTAB.GetLength(1); y++)
{
modulus[x, y] = Modulus(fourierTAB[x, y].Real, fourierTAB[x, y].Imaginary);
}
}
modulus = Normalize(modulus, modulus.GetLength(0), modulus.GetLength(1));
for (int x = 0; x < source.Width; x++)
{
for (int y = 0; y < source.Height; y++)
{
byte color = Convert.ToByte(modulus[x, y]);
fasterBitmapMask.SetPixel(x, y, Color.FromArgb(color, color, color));
}
}
fourierTAB = ShiftComplex(fourierTAB);
fourierTAB = ifft2(fourierTAB);
for (int x = 0; x < fourierTAB.GetLength(0); x++)
{
for (int y = 0; y < fourierTAB.GetLength(1); y++)
{
modulus[x, y] = Modulus(fourierTAB[x, y].Real, fourierTAB[x, y].Imaginary);
}
}
for (int x = 0; x < source.Width; x++)
{
for (int y = 0; y < source.Height; y++)
{
if (modulus[x, y] > 254)
{
modulus[x, y] = 255;
}
if (modulus[x, y] < 0)
{
modulus[x, y] = 0;
}
byte color = Convert.ToByte(modulus[x, y]);
fasterBitmapResult.SetPixel(x, y, Color.FromArgb(color, color, color));
}
}
fasterBitmapResult.UnlockBits();
fasterBitmapMask.UnlockBits();
return(new Tuple <Image, Image>(result, resultMask));
}