Image Processing Toolbox

Transforms

The usual mathematical representation of an image is a function of two spatial variables:

. The value of the function at a particular location

represents the intensity of the image at that point. The term transform refers to an alternative mathematical representation of an image.
This section defines several important transforms and shows examples of their application to image processing. Topics covered include

Terminology	Provides definitions of image processing terms used in this section
Fourier Transform	Defines the Fourier transform and some of its applications in image processing
Discrete Cosine Transform	Describes the Discrete Cosine Transform (DCT) of an image and its application, particularly in image compression
Radon Transform	Describes how the Image Processing Toolbox `radon` function computes projections of an image matrix along specified directions.

Computing the Frequency Response of a Filter Terminology