Cross Color

Cross Color [ ˈkɹɒs ˈkʌlə ] is an English term for shimmering color effects on structures of a certain size - such as coarsely woven or finely checked textiles - in a color television picture transmitted by analogue. A rainbow effect occurs on an NTSC image when the pattern slowly moves sideways. With PAL, fine patterns cause alternating red and green areas and with SECAM intense blue and yellow flashes of color (Secam thunderstorms).

These arise from the fact that fine luminance structures signal components in the vicinity of the color subcarrier ( English color cause, which are then misinterpreted at the receiver as a color signal). The reverse is called Cross Luminance .

Cross Color is in current TV applications with comb filters ( comb filter reduces), which both NTSC - as well as for PAL exist signals. By using modern 3D comb filters, the cross-color effect can be almost eliminated.

The effect can also be prevented at the transmitter end by removing the disruptive components from the brightness signal.

This effect no longer occurs with digital television, provided that the signal from the camera to the screen is never processed as a conventional analog television signal.

See also : moiré effect