Color television reception contact with color correction circuits and methods for improving the lack of color reproduction or. For the reduction of color discrepancies in regions of high color production using aet inferierter high frequency correction signal components

摘要

A color television receiving system for NTSC-type signals is provided with signal processing circuitry and methods for reducing the visibility of color infidelities, such as over-modulation, rectification, desaturation, and inadequate highs, which are visible in regions of high color saturation. Such infidelities are substantially reduced by effectively supplementing either the chrominance or the primary color signals with inferred high frequency chrominance components derived from signal information discovered to be inherently available in NTSC-type signals and their implicit constraints. Specifically, it has been found that in regions of high color saturation, high frequency chrominance components can be scaled from the high frequency portion of the received monochrome signal in accordance with the respective ratios of the value of the received reduced bandwidth chrominance signal to the value of a comparable low frequency component of the received monochrome signal. Alternatively, inferred high frequency primary color components can be analogously derived. A variety of specific circuit embodiments and methods can be used to derive suitable inferred high frequency components.