Television standards

In analog television, chrominance is encoded into a video arresting application a subcarrier frequency. Depending on the video standard, the chrominance subcarrier may be either quadrature-amplitude-modulated (NTSC and PAL) or frequency-modulated (SECAM).

In the PAL system, the blush subcarrier is 4.43 MHz aloft the video carrier, while in the NTSC arrangement it is 3.58 MHz aloft the video carrier. The NTSC and PAL standards are the a lot of frequently used, although there are added video standards that apply altered subcarrier frequencies. For example, PAL-M (Brazil) uses a 3.58 MHz subcarrier, and SECAM uses two altered frequencies, 4.250 MHz and 4.40625 MHz aloft the video carrier.

The attendance of chrominance in a video arresting is adumbrated by a blush access arresting transmitted on the aback porch, just afterwards accumbent synchronization and afore anniversary band of video starts. If the blush access arresting were arresting on a television screen, it would arise as a vertical band of a actual aphotic olive color. In NTSC and PAL, hue is represented by a appearance about-face of the chrominance arresting about to the blush burst, while assimilation is bent by the amplitude of the subcarrier. In SECAM (R'-Y') and (B'-Y') signals are transmitted alternately and appearance does not matter.

Chrominance is represented by the U-V blush even in PAL and SECAM video signals, and by the I-Q blush even in NTSC.