ABSTRACT
In the previous chapters, we focused on images in spatial domain,
i.e., the physical world. In this chapter, we will learn about the fre-
quency domain. The process of converting an image from spatial do-
main to frequency domain provides valuable insight into the nature of
the image. In some cases, an operation can be performed more effi-
ciently in the frequency domain than in spatial domain. We introduce
the various aspects of Fourier transform and its properties. We focus
exclusively on filtering an image in the frequency domain. Interested
readers can refer to [7],[97],[102] etc. for more in-depth treatment of
Fourier transformation.
