S Video To Television Views

General Goods

Separate Video,[1] more commonly known as S-Video and Y/C, and still often referred to by JVC, who introduced the DIN-connector pictured, as both an S-VHS connector [2] and as Super Video [3] is an analog video transmission scheme, in which video information is encoded on two channels: luma (luminance, intensity) and chroma (color). This is in contrast with lower-quality composite video, in which video information is encoded on one channel, and higher-quality component video, in which video information is encoded on three channels. S-Video carries standard definition video (typically at 480i or 576i resolution), but does not carry audio on the same cable.

The 4-pin mini-DIN connector (shown at right) is the most common of several S-Video connector types. Other S-Video connector variants include 7-pin locking dub connectors used on many professional S-VHS machines, and dual Y and C BNC connectors, often used for S-Video patch bays. Early Y/C video monitors often used RCA connectors that were switchable between Y/C and composite video input. Though the connectors are different, the Y/C signals for all types are compatible.

In composite video, the luminance signal is low-pass filtered to prevent crosstalk between high-frequency luminance information and the color subcarrier. S-Video maintains the two as separate signals, so that detrimental low-pass filtering is unnecessary. This increases bandwidth for the luminance information, and also subdues the color crosstalk problem. The infamous dot crawl is eliminated. This means that S-Video leaves more information from the original video intact; thus, it offers an improved image reproduction compared to composite video.

Due to the separation of the video into brightness and color components, S-Video is sometimes considered a type of component video signal; however, it is also the poorest, quality-wise, being far surpassed by the more complex component video schemes, such as RGB. What distinguishes S-Video from these better component-video schemes is that S-Video carries the color information as one signal. This means that the color has to be encoded in some way, and as such, NTSC, PAL, and SECAM signals are all decidedly different through S-Video. Thus, for full compatibility, the connected devices not only have to be S-Video compatible, but also compatible in terms of color encoding. In addition, S-Video suffers from reduced color resolution. NTSC S-Video color resolution is typically 120 lines horizontal (approximately 160, pixels edge-to-edge)[citation needed], versus 250 lines horizontal for the Rec. 601-encoded signal of a DVD, or 30 lines horizontal for standard VCRs.