Introduction

For our last problem domain of the term we'll take a look at image processing. Not a formal introduction to digital image processing, since to do that justice would take more mathematical background that you have at the moment. Instead we'll cherry pick a few interesting problems that are also accessible.

A digital image is a two dimensional array of pixels. Pixel stands for "picture element", and each pixel represents one point of light. There a lot of possible ways of describing a point of light. Physics students might think of wavelength and amplitude, but digital systems have taken their lead from the human visual system which has receptors for different wavelengths of light, and commonly represents them using the magnitudes of their red, green and blue components. Thus each pixel can be represented by a three-tuple: (R, G, B). We'll simplify things further and only work with "black and white" (actually grey scale, or monochrome) images, so our pixels will be represented by a single number giving their brightness or luminance.