What Is S-Video?

Standard-definition S-video is declining in popularity

Close-up of s-video cable
Evan-Amos / Wikimedia Commons / Public Domain

S-video is an analog (nondigital) video signal. This standard definition video is typically 480i or 576i. Unlike composite video, which carries all the video data in one signal, S-video carries brightness and color information as two separate signals. Because of this separation, video transferred by S-video is higher quality than that transferred by composite video. S-video has a variety of standard-definition uses, including connecting computers, DVD players, video consoles, video cameras and VCRs to TVs.

About S-Video

To put S-video performance in perspective, while it is a better option than composite cables—the familiar red, white and yellow coded cables—it is still not as good as the performance of component cables, the red, green, and blue coded cables. An S-video cable carries only a video signal. Sound must be carried by a separate audio cable.

How S-Video Works

So, how does it work? The S-video cable transmits video via two synchronized signal and ground pairs, named Y and C.

  • Y is the luma signal, which carries the luminance, which refers to the brightness or black-and-white elements of the video, and it includes horizontal and vertical synchronization pulses.
  • C is the chroma signal, which carries the chrominance, which refers to the color of the picture. This portion of the signal includes both the saturation and the hue elements of the video.

To use S-video to connect audiovisual equipment, both devices must support S-video and have S-video ports or jacks. An S-video cable connects the two devices.

S-video has become less popular since the advent of HDMI.

Note: S-video is also known as "separate video" and "Y/C" video.