Suppose I compute phase spectrum from the fftn function in MATLAB as
image1=imread('cameraman.tif');
figure,imshow(image1);
fourier_transform=fft2(image1);%take fourier transform of gray scale image
phase_spectrum=exp(1j*angle(fourier_transform));
imshow(phase_spectrum, [])
Here, by using imshow(phase_spectrum,[])
we first
discard the imaginary part and then normalize.
But why do we discard the imaginary part of the phase spectrum ? Whether it's spectrum is same as real part with 90 degree phase shift ?
Is it not useful ? Also,what should be done to get whole phase spectrum not just real part of it?