Digital Images

Why

We want to represent images.

Definitions

A binary image is a two-dimensional array in $\set{0, 1}$. We call the first coordinate of the shape the height and the second coordinate the width of the image. A grayscale image is a two-dimensional array in $\set{0, \dots , n}$, in which $n$ represents full saturation and all integers less than $n$ represent increasing saturation.

An RGB digital color is a length three sequence of bit strings. The terms of the color are known as the channels. So, for example, the first term of the sequence is the first channel, the second term is the second channel, and the third term is the third channel.

An RGB digital image is a two-dimensional array in the set of RGB digital colors. The image channels are the two-dimensional array whose values are those of the corresponding channel in the original image. So, for example, the first channel image is the grayscale image whose values are the first channel of the original digital image.

We refer to any of these (binary images, grayscale images, RGB digital images) as digital images, or often, as images.