al. 1996. "Tutorial Review, 35. Hill, K. O., B. Malo, and F. Bilodeau, 14. Hentschel, C. 1989. Fiber optics UV-Written In-Fiber Bragg Gratings," et al. 1993. "Bragg Gratings Fabricated handbook. Boeblingen, Germany: Optical and Quantum Electronics 28: in Monomode Photosensitive Optical Hewlett Packard. 93-135. Fiber by UV Exposure Through 15. Allard, F. C. 1990. Fiber optics a Phase Mask," Applied Physics Letters 27. Hill, K. O., D. C. Johnson, and handbook. For engineers and scientists. 62(10): 1035-1037. F Bilodeau, et al. 1987. "Narrow- New York: McGraw-Hill. Section Seven Section Seven Section Seven Section Seven Section Seven Video and image processing This page intentionally left blank Chapter 7.1 Introduction to video Keith Jack Although there are many variations and implementation occupied 3x more bandwidth than the current gray-scale techniques, video signals are just a way of transferring solution, SO alternate methods were developed that led visual information from one point to another. The to using Y, R-Y, and G-Y data to represent color in- information may be from a VCR, DVD player, a channel formation. A technique was then developed to transmit on the local broadcast, cable television, or satellite this Y, R-Y, and G-Y information using one signal, in- system, the Internet, or one of many other sources. stead of three separate signals, and in the same band- Invariably, the video information must be transferred width as the original gray-scale video signal. This from one device to another. It could be from a satellite composite video signal is what the NTSC, PAL, and set-top box or DVD player to a television. Or it could be SECAM video standards are still based on today. from one chip to another inside the satellite set-top box Today, even though there are many ways of representing or television. Although it seems simple, there are many video, they are still all related mathematically to RGB. different requirements, and therefore many different These variations are discussed in more detail in Chapter