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 image that stores two values, or a color image that stores three values. These values are usually between 0
and 255
in an integer number, but you can use other ranges, for example 0
to 1
in floating point numbers, as in high dynamic range imaging...