Image processing-a problem?

Hey everyone,

I was just wondering why when the magnitude of an image is zero, the phase is so noisy?

[Youssef Khmou]

hi Tina,

that is general question, can you be more specific, you mean when computing 2D Fourier transform of clean or noisy signal ?

[Tina]

Yes, I am using imagesc(angle(mydata)) and mydata is a fft transform of my data.

[Youssef Khmou]

ok, but phase has meaning when talking about periodic signals (1d or 2d) an image can not be considered as periodic signal, so of course the phase will look like rv , do you obtain something like :

I=im2double(imread('circuit.tif'));
dI=fft2(I);
P=angle(dI);
imagesc(P)
?

[Tina]

yes