# US 8,570,337 B2 · Color corrector, video display device, and color correction method > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 8,570,337 B2 - Document ID: US8570337B2 - Status: Granted - Kind: B2 - Application number: 13/558,993 - Filed: 2012-07-26 - Published: 2012-11-15 - Granted: 2013-10-29 - Earliest claimed: 2010-02-12 - Assignees: Panasonic Corporation - Applicants: Shinichi Tomioka; Nobuko Fujita - Inventors: Shinichi Tomioka; Nobuko Fujita - Web page: https://patentgrep.com/patent/US8570337B2 ## CPC - H04N 9/73: Colour balance circuits, e.g. white balance circuits or colour temperature control (camera processing pipelines for colour balance H04N23/88) - G09G 5/02: characterised by the way in which colour is displayed {(details of colour display specific for CRTs G09G1/28; specific for flat matrix panels other than liquid crystal displays G09G3/2003; specific for liquid crystal displays G09G3/3607)} - H04N 1/60: Colour correction or control {(H04N1/54 takes precedence)} - H04N: PICTORIAL COMMUNICATION, e.g. TELEVISION - G09G: ARRANGEMENTS OR CIRCUITS FOR CONTROL OF INDICATING DEVICES USING STATIC MEANS TO PRESENT VARIABLE INFORMATION (arrangements for transferring data between digital computers and displays G06F3/14; static indicating arrangements comprising an association of a number of separate sources or light control cells G09F9/00; static indicating arrangements comprising integral associations of a number of light sources H01J, H01K, H10H, H05B33/12; scanning, transmission or reproduction of documents or the like, e.g. facsimile transmission, details thereof H04N1/00) ## Abstract Color correction according to the present disclosure performs correction by adding a predetermined correction value to an input value of a component to be corrected, which is one of a plurality of components for representing a color with a predetermined color space, and outputs a corrected value. The color correction includes calculating an unadjusted correction value based on the input value; and adjusting the unadjusted correction value calculated in the calculating the unadjusted correction value so that the corrected value does not decrease with an increase in the input value, and outputting the adjusted value as the predetermined correction value. ## Claims ### Claim 1 An integrated circuit for performing color correction of a video input signal including a plurality of components for representing a color with a predetermined color space, performing correction by adding a predetermined correction value to an input value of one of the components to be corrected where the input value ranges from a correction region minimum value to a correction region maximum value which is greater than the correction region minimum value, and outputting a corrected value, comprising: a correction value calculator configured to calculate an unadjusted correction value based on the input value; and a correction value adjuster configured to adjust the unadjusted correction value calculated by the correction value calculator so that the corrected value does not decrease with an increase in the input value and ranges from the correction region minimum value to the correction region maximum value, and output the adjusted value as the predetermined correction value, wherein the unadjusted correction value: ranges from a predetermined maximum correction value to 0 with a slope less than −1 relative to the input value, where the input value is within a range from a first value to a second value MA, and is equal to or less than the maximum correction value with a slope of −1 or more relative to the input value, where the input value is out of the range from the first value to the second value MA, and the correction value adjuster outputs the unadjusted correction value as the predetermined correction value without any change, where |(the unadjusted correction value)| is equal to or less than |MA−(the input value)|. ### Claim 2 (depends on 1) The integrated circuit of claim 1, wherein the correction value adjuster outputs |MA−(the input value)| as the predetermined correction value, where |(the unadjusted correction value)| is more than |MA−(the input value)|. ### Claim 3 (depends on 1) The integrated circuit of claim 1, wherein the predetermined color space is an HSV space representing a color with a hue component, a saturation component, and a brightness component, the component to be corrected is the hue component, and the correction value calculator calculates, as the unadjusted correction value, a value obtained by multiplying a hue function output amount according to the hue component by a saturation function output amount according to the saturation component by a brightness function output amount according to the brightness component by a predetermined offset value. ### Claim 4 (depends on 1) A video display device comprising: the integrated circuit of claim 1, and a display configured to display a video image based on a video signal including a corrected value output from the color corrector as the component to be corrected. ### Claim 5 An integrated circuit for performing color correction of a video input signal including a plurality of components for representing a color with a predetermined color space, performing correction by adding a predetermined correction value to an input value of one of the components to be corrected where the input value ranges from a correction region minimum value to a correction region maximum value which is greater than the correction region minimum value, and outputting a corrected value, comprising: a correction value calculator configured to calculate an unadjusted correction value based on the input value; and a correction value adjuster configured to adjust the unadjusted correction value calculated by the correction value calculator so that the corrected value does not decrease with an increase in the input value and ranges from the correction region minimum value to the correction region maximum value, and output the adjusted value as the predetermined correction value, wherein the unadjusted correction value: ranges from 0 to a predetermined minimum correction value with a slope less than −1 relative to the input value, where the input value is within a range from a first value MI to a second value, and is equal to or more than the minimum correction value with a slope of −1 or more relative to the input value, where the input value is out of the range from the first value MI to the second value, and the correction value adjuster outputs the unadjusted correction value as the predetermined correction value without any change, where |(the unadjusted correction value)| is equal to or less than |(the input value)−MI|. ### Claim 6 (depends on 5) The integrated circuit of claim 5, wherein the correction value adjuster outputs −|(the input value)−MI| as the predetermined correction value, where |(the unadjusted correction value)| is more than |(the input value)−MI|. ### Claim 7 (depends on 5) The integrated circuit of claim 5, wherein the predetermined color space is an HSV space representing a color with a hue component, a saturation component, and a brightness component, the component to be corrected is the hue component, and the correction value calculator calculates, as the unadjusted correction value, a value obtained by multiplying a hue function output amount according to the hue component by a saturation function output amount according to the saturation component by a brightness function output amount according to the brightness component by a predetermined offset value. ### Claim 8 (depends on 5) A video display device comprising: the integrated circuit of claim 5, and a display configured to display a video image based on a video signal including a corrected value output from the color corrector as the component to be corrected. ### Claim 9 A color correction method of performing color correction of a video input signal including a plurality of components for representing a color with a predetermined color space, performing correction by adding a predetermined correction value to an input value of one of the components to be corrected where the input value ranges from a correction region minimum value to a correction region maximum value which is greater than the correction region minimum value, and outputting a corrected value, the method comprising: calculating, by a processor, an unadjusted correction value based on the input value; and adjusting the unadjusted correction value calculated in the calculating the unadjusted correction value so that the corrected value does not decrease with an increase in the input value and ranges from the correction region minimum value to the correction region maximum value, and outputting the adjusted value as the predetermined correction value, wherein the unadjusted correction value: ranges from a predetermined maximum correction value to 0 with a slope less than −1 relative to the input value, where the input value is within a range from a first value to a second value MA, and is equal to or less than the maximum correction value with a slope of −1 or more relative to the input value, where the input value is out of the range from the first value to the second value MA, and in the adjusting the unadjusted correction value, the unadjusted correction value is output as the predetermined correction value without any change, where |(the unadjusted correction value)| is equal to or less than |MA−(the input value)|. ### Claim 10 (depends on 9) The method of claim 9, wherein in the adjusting the unadjusted correction value, |MA−(the input value)| is output as the predetermined correction value, where |(the unadjusted correction value)| is more than |MA−(the input value|. ### Claim 11 (depends on 9) The method of claim 9, wherein the predetermined color space is an HSV space representing a color with a hue component, a saturation component, and a brightness component, the component to be corrected is the hue component, and in the calculating the unadjusted correction value, a value obtained by multiplying a hue function output amount according to the hue component by a saturation function output amount according to the saturation component by a brightness function output amount according to the brightness component by a predetermined offset value is calculated as the unadjusted correction value. ### Claim 12 A color correction method of performing color correction of a video input signal including a plurality of components for representing a color with a predetermined color space, performing correction by adding a predetermined correction value to an input value of one of the components to be corrected where the input value ranges from a correction region minimum value to a correction region maximum value which is greater than the correction region minimum value, and outputting a corrected value, the method comprising: calculating, by a processor, an unadjusted correction value based on the input value; and adjusting the unadjusted correction value calculated in the calculating the unadjusted correction value so that the corrected value does not decrease with an increase in the input value and ranges from the correction region minimum value to the correction region maximum value, and outputting the adjusted value as the predetermined correction value, wherein the unadjusted correction value: ranges from 0 to a predetermined minimum correction value with a slope less than −1 relative to the input value, where the input value is within a range from a first value MI to a second value, and is equal to or more than the minimum correction value with a slope of −1 or more relative to the input value, where the input value is out of the range from the first value MI to the second value, and in the adjusting the unadjusted correction value, the unadjusted correction value is output as the predetermined correction value without any change, where |(the unadjusted correction value)| is equal to or less than |(the input value)−MI|. ### Claim 13 (depends on 12) The method of claim 12, wherein in the adjusting the unadjusted correction value, −|(the input value)−MI| is output as the predetermined correction value, where |(the unadjusted correction value)| is more than |(the input value)−MI|. ### Claim 14 (depends on 12) The method of claim 12, wherein the predetermined color space is an HSV space representing a color with a hue component, a saturation component, and a brightness component, the component to be corrected is the hue component, and in the calculating the unadjusted correction value, a value obtained by multiplying a hue function output amount according to the hue component by a saturation function output amount according to the saturation component by a brightness function output amount according to the brightness component by a predetermined offset value is calculated as the unadjusted correction value.