Still Image Compression*

Digital representation of images is important for digital transmission and storage on different media such as magnetic or laser disks. However, pictorial material requires vast amounts of bits if represented through direct quantization. As an example, an SVGA color image requires 33 6003 800 bytes¼ 144 Mbytes when each color component is quantized using 1 byte per pixel, the amount of bytes that can be stored on one standard 3.5 in. diskette. It is therefore evident that ‘‘compression’’ (often called ‘‘coding’’) is necessary for reducing the amount of data [33].