Learn OpenCV 4 by Building Projects - Second Edition

Images and matrices

The most important structure in computer vision is, without doubt, the images. The image in a computer vision is the representation of the physical world captured with a digital device. This picture is only a sequence of numbers stored in a matrix format (refer to the following diagram). Each number is a measurement of the light intensity for the considered wavelength (for example, red, green, or blue in color images) or for a wavelength range (for panchromatic devices). Every point in an image is called a pixel (for a picture element), and each pixel can store one or more values depending on whether it is a black and white image (also referred to as a binary image) that stores only one value, such as 0 or 1, a grayscale-level ...