Scan and video converters transform computer-video signals into a television-compatible format. They are sometimes called PC to TV converters or PC to video converters, a reference to their use with personal computers (PCs). Product specifications for scan and video converters include input and output parameters, as well as power requirements, mounting styles, and controls. Refresh rate is also an important specification to consider.
Scan and video converters can receive RGB, HDTV, radar, or sonar input signals. RGB is a type of component video output in which red, green, and blue image components are transmitted as separate signals over three separate wires. This allows for full bandwidth for each component. High definition (HD) is a digital video image with at least two times the resolution of the National Television System Committee (NTSC) standard or Phase Alternative Line (PAL) video. The high definition television (HDTV) aspect ratio is 16:9.
In addition to input signal type, scan and video converters differ in terms of resolution. There are five main choices: video graphics array (VGA), super video graphics array (SVGA), extended graphics array (XGA), super extended graphics array (SXGA), and ultra extended graphics array (UXGA). Each graphics standard supports a specific color palette and maximum resolution, which is measured in pixels.
Video outputs for scan and video converters are defined according to type and format. There are many choices for type. These include RGB, HDTV, NTSC and PAL as well as SECAM, RS170, and CCIR. Variants such as 3.58/4.43 NTSC are also available. Output formats for scan and video converters range from RGB and composite video to Y PbPr, and Y/C (S-video). Y Pb-Pr is a component video format in which three signals (Y, R-Y, and B-Y) are transmitted via separate cables. S-Video or Y/C outputs contain two separate signals, luminance (Y) and color (C) transmitted on two separate cables.
Selecting Scan and Video Converters
Power requirements, mounting styles, and controls are specifications to consider when selecting scan and video converters. Some devices require 115 VAC or 230 VAC power. Others require a DC power source for proper operation. Available mounting styles include desktop or stand-alone, panel or chassis mount, and rack mount. There are many different device controls. These include brightness, contrast, saturation, zoom, freeze, and genlock adjustment. Scan and video converters with a built-in test pattern and remote control support are also available.