Abstract: Improvements in a phase responsive video parameter control system for correcting hue, saturation and luminance of a phase encoded composite video signal are disclosed. The system has a phase detector that detects which of a plurality of color intervals or hue bands the instantaneous signal falls in. Luminance, hue and saturation corrections for each band are applied to the uncorrected video. The improvements include correction signal selection circuit that select the correction signals twice per subcarrier cycle, a damping circuit that smooths the transition between two correction signals when the hue moves to a different color interval or band, and a phase shifter that allows the centers of the bands to be moved without changing the width of the band.

Abstract: A luminance selection apparatus for correcting the hue, saturation and luminance of an input color video signal as a function of the luminance of the signal. The system allows setting and storing luminance threshold levels which are used in conjunction with other color selection circuitry to select a region of interest in a video image being displayed. An operator selects a particular hue of interest with color selection circuitry, and then sets a luminance threshold level which discriminates between the same or similar hues in a video image which differ in luminance. In one embodiment, pre-stored digital correction values are retrieved from memory and converted into analog correction signals which modify the phase, amplitude and DC level of the composite video signal only when the input luminance exceeds the threshold level.

Abstract: A luminance selection apparatus for correcting the hue, saturation and luminance of an input color video signal as a function of the luminance of the signal. The system allows setting and storing luminance threshold levels which are used in conjunction with other color selection circuitry to select a region of interest in a video image being displayed. An operator selects a particular hue of interest with color selection circuitry, and then sets a luminance threshold level which discriminates between the same or similar hues in a video image which differ in luminance. In one embodiment, pre-stored digital correction values are retrieved from memory and converted into analog correction signals which modify the phase, amplitude and DC level of the composite video signal only when the input luminance exceeds the threshold level.

Abstract: A phase responsive video parameter control system operative for correcting hue, saturation, and luminance of a phase encoded component of a composite video signal. A digital phase detector detects the instantaneous hue of the video image, and provides a signal which selects which one of a plurality of color intervals or bands the detected instantaneous hue falls in. Prestored digital correction values associated with the selected color interval are retrieved from memory and converted into analog correction signals which modify the phase, amplitude, and DC level of the composite video signal. New digital correction values, which reflect operator control panel adjustments, may be loaded into memory during the vertical retrace interval, thereby allowing frame-by-frame color correction.

Abstract: A phase responsive video parameter control system operative for correcting hue, saturation, and luminance of a phase encoded component of a composite video signal. A digital phase detector detects the instantaneous hue of the video image, and provides a signal which selects which one of a plurality of color intervals or bands the detected instantaneous hue falls in. Prestored digital correction values associated with the selected color interval are retrieved from memory and converted into analog correction signals which modify the phase, amplitude, and DC level of the composite video signal. New digital correction values, which reflect operator control panel adjustments, may be loaded into memory during the vertical retrace interval, thereby allowing frame-by-frame color correction.

Abstract: A phase responsive video parameter control system operative for correcting hue, saturation, and luminance of a phase encoded component of a composite video signal. A digital phase detector detects the instantaneous hue of the video image, and provides a signal which selects which one of a plurality of color intervals or bands the detected instantaneous hue falls in. Prestored digital correction values associated with the selected color interval are retrieved from memory and converted into analog correction signals which modify the phase, amplitude, and DC level of the composite video signal. New digital correction values, which reflect operator control panel adjustments, may be loaded into memory during the vertical retrace interval, thereby allowing frame-by-frame color correction.