Method and apparatus for uniform saturation, hue and luminance correction

摘要

Video signal color correction is accomplished by selecting for color correction areas of the chrominance plane defining sectors in polar coordinants. Both the angle and the width of the sector can be changed to select precisely the desired signals for color correction. Specifically, component color difference video signals which only lie within a fixed hue sector are transmitted from an input to an output. Responsive to a first control signal, the difference signals are rotated through an angle which corresponds to a selected hue sector relative to the fixed hue sector in which the component color signals are to be corrected. The rotated difference signals are applied to the input to produce at the output an isolated color signal only when the difference signals lie within the selected hue sector. The width of the fixed hue sector is reduced responsive to a second control signal. Thus, the first and second control signals permit selection of the angle and the width of the sector in which the difference signals are to be corrected.