EE4206/EE5806 Fourier spectrum

EE4206/EE5806 Digital Image Processing

notes on Fourier spectrum :
notes on ( Gonzales and Wood 2008 ) Digital Image Processing, 3rd ed.

The plot of |F(u)| as a function of frequency.

The key properties to note are that the locations of the zeros of both F(u) and |F(u)| are inversely proportional to the width, W, of the " box " function, that the height of the lobes decreases as a function of distance from the origin, and that the function extends to infinity for both positive and negative values of u.

These properties are quite helpful in interpreting the spectra of two-dimensional fourier teansforms if images.