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US4953008A Expired / Lapsed US ⏱️ 0.0 years remaining

Method and apparatus for uniform saturation, hue and luminance correction

Assignee: MSCL Inc
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Filing: 1989-04-19
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Granted: 1990-08-28
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Expires: 2009-04-19
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Abstract

Abstract 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.

Inventors

  • 👤 Michael C. Kaye

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-10-30 00:44
CPC Classifications
H; H04; H04N; H04N9/00; H04N9/64; H04N9/643; H04N9/68

Claims Analysis

Total Claims: 13
Claim 1
Independent Claim 137 words
A color correction system for manipulating signals representing colors, the system comprising: input means for accepting signals representing colors defining hues and respective saturations; a color correction circuit for accepting the signals from the input, and including: color selection means for producing from the input signals a selected signal at an output proportional to the saturation of a portion of the input single in a selected hue region, signal processing means coupled to the output of the color selection means for accepting the selected signal and for processing the signal to produce an output signal having substantially constant saturation, and means for providing the output signal as a correction signal; and means for combining the signals from the input means with the correction signal and producing resultant signals and for passing the resultant signals to an output.
Claim 2
Dependent Claim 137 words
A color correction system for manipulating signals representing colors, the system comprising: input means for accepting signals representing colors defining hues and respective saturations; a color correction circuit for accepting the signals from the input, and including: color selection means for producing from the input signals a selected signal at an output proportional to the saturation of a portion of the input single in a selected hue region, signal processing means coupled to the output of the color selection means for accepting the selected signal and for processing the signal to produce an output signal having substantially constant saturation, and means for providing the output signal as a correction signal; and means for combining the signals from the input means with the correction signal and producing resultant signals and for passing the resultant signals to an output.
Claim 3
Dependent Claim 44 words
The system of claim 1 wherein the color selection means includes means responsive to a first control signal for defining hue angle, and means responsive to a second control signal for defining a hue sector containing the hue angle for isolating the selected signal.
Claim 4
Dependent Claim 27 words
The system of claim 1 wherein the signal processing means comprises a clipping circuit for clipping the signal to produce a signal having a substantially constant amplitude.
Claim 5
Dependent Claim 23 words
The system of claim 3 wherein the signal processing means comprises means for increasing a gain of the signal before the clipping circuit.
Claim 6
Dependent Claim 24 words
The system of claim 4 wherein the correction signal producing means includes an R-Y multiplier and a B-Y multiplier for accepting the clipped signal.
Claim 7
Dependent Claim 38 words
The system of claim 1 wherein the correction signal providing means includes means for multiplying the output signal by at least one correction factor to adjust at least one of the hue and saturation of the correction signal.
Claim 8
Dependent Claim 24 words
The system of claim 8 wherein the correction signal providing means includes an R-Y multiplier and a B-Y multiplier for accepting the output signal.
Claim 9
Dependent Claim 36 words
The system of claim 1 wherein the correction signal providing means includes means for combining the output signal with a hue and saturation control signal to produce a correction signal having a desired hue and saturation.
Claim 10
Dependent Claim 137 words
A color correction system for manipulating signals representing colors, the system comprising: input means for accepting signals representing colors defining hues and respective saturations; a color correction circuit for accepting the signals from the input, and including: color selection means for producing from the input signals a selected signal at an output proportional to the saturation of a portion of the input signals in a selected hue region, signal processing means coupled to the output of the color selection means for accepting the selected signal and for clipping the signal to produce an output signal having substantially constant saturation and means for providing the output signal as a correction signal; and means for combining the signals from the input means with the correction signal and producing resultant signals and for passing the resultant signals to an output.
Claim 11
Dependent Claim 137 words
A color correction system for manipulating signals representing colors, the system comprising: input means for accepting signals representing colors defining hues and respective saturations; a color correction circuit for accepting the signals from the input, and including: color selection means for producing from the input signals a selected signal at an output proportional to the saturation of a portion of the input signals in a selected hue region, signal processing means coupled to the output of the color selection means for accepting the selected signal and for clipping the signal to produce an output signal having substantially constant saturation and means for providing the output signal as a correction signal; and means for combining the signals from the input means with the correction signal and producing resultant signals and for passing the resultant signals to an output.
Claim 12
Dependent Claim 45 words
The system of claim 6 wherein the color selection means includes means responsive to a first control signal for defining a hue angle, and means responsive to a second control signal for defining a hue sector containing the hue angle for isolating the selected signal.
Claim 13
Dependent Claim 32 words
The system of claim 1 wherein the correction signal providing means includes mean for combining the output signal with a luminance control signal to produce a correction signal for a luminance signal.

USPTO Annuity & Maintenance Windows

Annuity Stage Window Opens Payment Deadline Surcharge Period Until Estimated Fee Status
3.5 Years (Year 4) 1993-08-27 1994-02-26 1994-08-28 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 1997-08-27 1998-02-26 1998-08-28 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 2001-08-27 2002-02-26 2002-08-28 $7700.00 Window Closed / Lapsed

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