private static ComplexF[] GetImageFFTArray(Bitmap bitmap) {
float scale = 1F / (float) System.Math.Sqrt(bitmap.Width * bitmap.Height);
ComplexF[] data = new ComplexF [bitmap.Width * bitmap.Height * 4];
int offset = 0;
for( int y = 0; y < bitmap.Height; y ++ )
for( int x = 0; x < bitmap.Width; x ++ ) {
Color c = bitmap.GetPixel (x, y);
float s = 1F;
if( (( x + y ) & 0x1 ) != 0 ) {
s = -1F;
}
data [offset++] = new ComplexF( c.A * s / 256F, 0);
data [offset++] = new ComplexF( c.R * s / -256F, 0);
data [offset++] = new ComplexF( c.G * s / 256F, 0);
data [offset++] = new ComplexF( c.B * s / -256F, 0);
}
Fourier.FFT3( data, 4, bitmap.Width, bitmap.Height, FourierDirection.Forward );
for( int i = 0; i < data.Length; i ++ ) {
data[i] *= scale;
}
return data;
}
#endregion
