Image Processing in Frequency Domain
The discrete Fourier transform is introduced to ﬁlter unwanted attributes of an image or signal such as from electronic noise or from atmospheric distortion. The discrete Fourier transform is represented by the Fourier matrix whose components are complex numbers. By using properties of complex numbers and matrices a number of important properties of the discrete Fourier and fast Fourier transform are derived. These are then used to ﬁlter in the frequency domain a number of images.