ed by the camera: red, green, and blue (RGB), respectively. However, more Chapter 3 Digital Video Transmission D Bits/sample C Frames Fig. 3.1 Digital video B Samples representation. commonly a new color space is created consisting of the luminance (black and white) com- ponent and two other chrominance (color) components as seen in the NTSC, PAL, and SECAM standards. The amount of color component compared to the luminance categorizes the image format. Image formats have a variety of options-for example: (1) CCIR-601 or 4:2:2 format where the number of horizontal chrominance pixels is half the luminance, and (2) SIF or 4:2:0 format where the horizontal resolution of the chrominance is halved and the vertical is divided by 4 (Ghanbari, 1999). Reducing the amount of color component clearly reduces the quality of the image, but such is the nature of the human eye (Pearson, 1975) that the renditions are generally indistinguishable from the full-resolution RGB. Image Size Images come in a variety of sizes depending on whether they use the NTSC or the PAL standard (ISO/IEC, 1995). They range from small thumbnails up to super-high definition. For example, sub-QCIF, QCIF, and CIF images have sizes 128 X 96, 176 X 144, and 352 X 288, and they find widespread use in multimedia applications. When it comes to entertainment systems, there is a variety of images sizes. With standard broadcast size, the PAL standard uses 720 X 576 and NTSC employs 720 X 480 (Ghanbari, 2003). With higher-definition enter- tainment systems, picture formats are often proprietary and await convergence of the standards. So-called HD-ready pictures are 1024 X 768, 720p is 1280 X 720, HD-ready 1080p is 1280 X 1080, HDV 1080i is 1440 X 1080, FULL-HD is 1920 X 1080, and 2160p or quad HDTV (super-high definition) is 3840 X 2160. This list is not exhaustive. Other innovations shortly to be offered include 3 DTV where the bandwidth required is up to twice that for standard monoscopic displays. Raw Digital Video: Motivation for Compression Table 3.1 illustr