Glossary Calibrate The process of standardizing a reference tool, such as a vectorscope or waveform monitor, so that any signal information that is displayed is measured accurately. Captioning/Closed Captioning Developed to aid the hearing impaired, the process of encoding and decoding typed text so that it may be displayed on a receiver or monitor. In the NTSC closed captioning system, the data is incorporated on line 21. Charge Coupled Device (CCD) A solid-state device or chip consisting of multiple sites operating as capacitors that convert light energy to electrical charges. Chroma Subsampling The sampling of the color or chroma information in an image less often than the luminance to reduce the amount of data to be stored or transmitted. Chrominance references. Pure color information without light or luminance
Color Bars A test signal that provides the necessary elements for visual setup of video equipment. The basic display includes a white or video-level reference, black-level reference, chroma levels, and hue information. Additional elements also may be included. Color Black/Black Burst A composite signal that combines the color subcarrier, horizontal sync, vertical sync, blanking, and a black video signal. Color Difference Signal The calculation of the quantity of chroma information in the signal minus the luminance (Y) information (i.e., R-Y, B-Y, and G-Y). Color Encoding Translating the color video information from its original state to a condensed form for recording and transmitting. Color Frame Pulse A pulse recorded on videotape that identifies the color frame cycle. Color Framing The phase or direction of the subcarrier signal with respect to the lines and fields that make up the color picture. In the NTSC system, the color frame is determined by the phase of
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