1.2.5 Image Processing
Digital image processing has been facilitated in a number of areas in medical practice and applications or research. Naturally, the expression refers to the use of the computer algorithms to perform analysis of digital images. For example digital image processing is used to determine the brightness of stars in pictures from telescopes, to determine the structure of a virus in a microscope image, and to produce highly accurate maps of the earth from satellite-gathered pictures [6]. There are a number of applications in medicine in cartography.The size of the physical area represented by a pixel is called the spatial resolution of the pixel. Each pixel has a value, and coordinates, which reveal its location in the image array. The images used are 1280 by 960 pixels. The minimum value a pixel can have is “0”, and the maximum depends on how the number is stored in the computer. One way is to store each pixel as a single bit, which means it can take only the values of “0” and “1” or black and white as shown in Figure 1.19 Another common way is to store each pixel as a byte, which consists of 8 bits. In this form, the maximum pixel value is 255.