S-Video Signals

S-Video Signals

S-Video, often referred to as Y/C, is a higher quality signal than Composite because it separates out the luminance and chrominance signals into separate channels, eliminating interference that can cause color distortions. The Luminance channel conveys "brightness", and the chrominance channel conveys "color" information (using a modulated sub-carrier just as in Composite).

The normal composite sync is present only in the luminance channel (sometimes denoted as Ys). S-Video still has an underlying standard such as PAL or NTSC that determines the number of lines per frame, field rate, etc, and for the most part can be tested in a similar fashion. However, certain measurements performed on Composite signals do not apply to S-Video due to the separation of Y and C signals.

Possible Signal Distortions

Transmitting the Y/C signals separately, as in S-Video, circumvents the error-prone separation process typically seen with composite video. For example, the effects in CVBS associated with remnants of chrominance data in the luminance data ("dot crawl"), or remnants of luminance data remaining in the chrominance ("rainbow" effects) are avoided in S-Video.