//******************************************************************
//******************************************************************
private void FFT_Click(object sender, EventArgs e)
{
//check user has loaded an image to edit
if (originalImage == null)
{
MessageBox.Show("Please select a valid image");
return;
}
Bitmap copy = new Bitmap((Bitmap)this.pBox.Image);
try
{
// create greyscale bitmap
var grayScaledImage = ComplexImage.ToGrayscale(copy);
var complexIm = ComplexImage.ConvertBitmapImageToComplex(grayScaledImage);
Fourier.FFT2D(complexIm, 1);
var transformedImage = ComplexImage.ConvertComplexImageToBitmap(complexIm);
this.pBox.Image = transformedImage;
}
catch (Exception ex)
{
MessageBox.Show($"Error: {0}", ex.Message);
}
}
public static void FFT2D(Complex[,] complexImage, int direction)
{
int width = complexImage.GetLength(0);
int height = complexImage.GetLength(1);
//check data size
if (
(!ComplexImage.IsPowerOfTwo(width)) ||
(!ComplexImage.IsPowerOfTwo(height))
)
{
throw new ArgumentException("Incorrect data length.");
}
//process the rows
Complex[] row = new Complex[width];
for (int j = 0; j < height; j++)
{
// copy row
for (int i = 0; i < width; i++)
{
row[i] = complexImage[i, j];
}
// transform it
FFT1D(direction, row);
// copy back
for (int i = 0; i < width; i++)
{
complexImage[i, j] = row[i];
}
}
// process the columns
Complex[] column = new Complex[height];
for (int i = 0; i < width; i++)
{
// copy row
for (int j = 0; j < height; j++)
{
column[j] = complexImage[i, j];
}
// transform it
FFT1D(direction, column);
// copy back
for (int j = 0; j < height; j++)
{
complexImage[i, j] = column[j];
}
}
}
