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Publisher Summary This chapter presents an overview of the engineering essentials of video techniques. Although there are many variations and implementation techniques, video signals are just a way of transferring visual information from one point to another. The information may be from a VCR, DVD player, a channel on the local broadcast, cable television, or satellite system, the Internet, cell phone, MP3 player, or one of many other sources. Invariably, the video information must be transferred from one device to another. A color space is a mathematical representation for a color. Initially, video contained only gray scale, or black-and-white, information. When color broadcasts were being developed, attempts were made to transmit color video using RGB (red, green, blue) color space data, but that technique occupied too much bandwidth so other alternative color spaces were developed. Component video is video using three separate color components, such as YCbCr (digital), YPbPr (analog), or R'G'B' (digital or analog). Composite video uses a single signal to contain color, brightness and timing information. Compression is an important part of video technology. MPEG stands for Moving Picture Experts Group, an international standards group that develops various compression algorithms. MPEG video compression takes advantage of the redundancy on a frame-by-frame basis of a normal video sequence. Many standards organizations are involved in specifying video standards, including Advanced Television Systems Committee (ATSC), Association of Radio Industries and Businesses (ARIB), Cable Television Laboratories, Video Electronics Standards Association (VESA), and Consumer Electronics Associations (CEA).

Publisher Summary This chapter provides an overview of the common video signal formats and their timing. It gives definitions of several terms related to video signals including SDTV (Standard Definition Television), NTSC (National Television System Committee), HDTV (High-Definition Television), active video, aspect ratio, and color bars. Digital component video is digital video that uses three separate color components, such as R'G'B' or YCbCr. In digital component video, the video signals are in digital form (YCbCr or R'G'B'), being encoded to composite NTSC, PAL, or SECAM only when it is necessary for broadcasting or recording purposes. 480i and 480p systems include interlaced analog composite video, progressive analog component video, interlaced digital component video, and progressive digital component video at 480 active scan lines per frame. 576i and 576p systems include analog composite video, interlaced analog component video, progressive analog component video, interlaced digital component video, and progressive digital component video at 576 active scan lines per frame. 720p systems include progressive analog component video and progressive digital component video at 720 active scan lines per frame. 1080i and 1080p systems include interlaced analog component video, progressive analog component video, interlaced digital component video, and progressive digital component video at 1080 active scan lines per frame.

Publisher Summary The chapter reviews the video timing, and the analog and digital representations of various video formats, including 480i, 480p, 576i, 576p, 720p, 1080i, and 1080p. They come in a wide variety of options, number of scan lines, interlaced vs. progressive, analog vs. digital, and so on. The chapter provides an overview of the common video signal formats and their timing. In a digital component video, the video signals are in digital form (YCbCr or R'G'B'), being encoded to composite National Television System Committee (NTSC), Phase Alternation Line (PAL), or Sequential Color with Memory (SECAM) only when it is necessary for broadcasting or recording purposes. For 8-bit systems, the values of 00H and FFH are reserved for timing information. For 10-bit systems, the values of 000H-003H and 3FCH-3FFH are reserved for timing information, to maintain compatibility with 8-bit systems.

Publisher Summary This chapter discusses the digital video and display electronics. Digital video comprises a series of orthogonal bitmap digital images displayed in rapid succession at a constant rate. In the context of video, these images are called frames. We measure the rate at which frames are displayed in FPS. Many analog and digital recording formats are in use, and digital video clips can also be stored on a computer file system as files that have their own formats. In addition to the physical format used by the data storage device or transmission medium, the stream of ones and zeros, which is sent, must be in a particular digital of which a number is available. Serial Data Transport Interface is a way of transmitting data packets over a Serial Digital Interface (SDI) datastream, which means that standard SDI infrastructure can be used. The video decoder decodes chroma and luma signal and is referred to as the decoder. The video encoder encodes the chroma and the luma back into the composite signal. Video decoders and encoders are generally specified in terms of video performance. Further, the best performance can be obtained by utilizing the native RGB component video rather than composite signals. Flat panel LCD-based displays have steadily increased over the past few years. The charge-coupled-device (CCD) and contact-image-sensor (CIS) are widely used in consumer imaging systems such as scanners and digital cameras. Touch screens have become widespread in hand-held PDAs and other computer products.

This chapter details the scanning, timing, sync structure, and picture structure of 576i25 video. The scanning and timing information applies to all variants of 576i25 video, both analog and digital. The sync information relates to component analog, composite analog, and composite digital systems. 576i video represents stationary or moving two-dimensional images sampled temporally at a constant rate of 25 frames per second. A frame comprises a total of 625 horizontal raster lines of equal duration uniformly scanned top to bottom and left to right, with 2:1 interlace to form a first field and a second field. Scanning lines in the second field are displaced vertically by half of the vertical sampling pitch, and delayed temporally by half of the frame time, from scanning lines in the first field. To define vertical sync, the frame is divided into intervals of halfline duration. Each halfline either contains no sync information, or commences with the assertion of a sync pulse having one of the three durations, each having a tolerance of ± 100 μs. Sync in 576i systems contains several differences from 480i sync.

This chapter analyzes the way in which an encoder forms U and V color difference components, the way in which modulated chroma (C) is formed, and the way in which a decoder demodulates back to U and V. The chapter outlines composite National Television System Committee (NTSC) and Phase Alternate Line (PAL) color encoding. The designers of NTSC color television intended that chroma would be based upon I and Q components. Nowadays, I and Q components are essentially obsolete, and U and V components are generally used. Y'UV coding is unique to composite NTSC and PAL: It is has no place in component video, HDTV, or computing.

This chapter details the scanning, timing, sync structure, and picture structure of 480i29.97 video. The scanning and timing information in this chapter applies to all variants of 480i video, both analog and digital. The sync information relates to component analog, composite analog, and composite digital systems. 480i video represents stationary or moving two-dimensional images sampled temporally at a constant rate of 30/1.001 frames per second. A frame comprises a total of 525 horizontal raster lines of equal duration uniformly scanned top to bottom and left to right. Scanning has 2:1 interlace to form a first, as well as a second field; scan lines in the second field are displaced vertically by half the vertical sampling pitch, and delayed temporally by half the frame time, from scanning lines in the first field. To define vertical sync, the frame is divided into intervals of halfline duration. Each halfline either contains no sync information or commences with the assertion of a sync pulse having one of three durations, each having a tolerance of ±0.100 μs.

This chapter draws attention to the concepts of Luma and color differences. It provides detailed information on the B'-Y' . R'-Y' components, the basis for P B P R and C B C R , P B P R components used for analog interface, and C B C R used for digital interface. The chapter explains that if two color difference components having excursions identical to luma are to be formed, then P B and P R color difference components are used. One method of extending the color gamut of an R'G'B' system is to allow components to excurse below zero and above unity. Rec. 1361 is based upon Rec. 709 primaries, but enables the RGB tristimulus components to excurse from -1/4 to +4/3. In discussing conversions between high-definition television (HDTV) and standard-definition television (SDTV), the chapter explains that the differences among the EBU, SMPTE, and Rec. primaries are negligible for practical purposes. New equipment should be designed to Rec. 709. Also, SDTV and HDTV have effectively converged to the transfer function specified in Rec. 709. Consequently, R'G'B' coding uses essentially identical parameters worldwide, for SDTV and HDTV.