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?