# US 2025/0095232 A1 · Human color discrimination for memory-efficient encoding in extended reality > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 2025/0095232 A1 - Document ID: US20250095232A1 - Status: Published application - Kind: A1 - Application number: 18/884,550 - Filed: 2024-09-13 - Published: 2025-03-20 - Earliest claimed: 2023-09-15 - Assignees: University of Rochester; New York University - Applicants: University of Rochester; New York University - Inventors: Yuhao Zhu; Qi Sun; Nisarg Ujjainkar; Ethan Shahan; Kenneth Chen; Budmonde Duinkharjav - Web page: https://patentgrep.com/patent/US20250095232A1 ## CPC - G09G 3/2007: {Display of intermediate tones} - G06F 3/013: {Eye tracking input arrangements (G06F3/015 takes precedence)} - G06T 7/90: Determination of colour characteristics - G06T 11/10: Texturing; Colouring; Generation of textures or colours (retouching, inpainting or scratch removal G06T5/77) - G09G 3/2003: {Display of colours (specific for liquid crystal displays G09G3/3607)} - G09G 2330/021: Power management, e.g. power saving - 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) - G06F: ELECTRIC DIGITAL DATA PROCESSING (computer systems based on specific computational models G06N) - G06T: IMAGE DATA PROCESSING OR GENERATION, IN GENERAL ## Abstract Memory-efficient encoding based on human-color perception can include calculating a plurality of two-dimensional boundaries in a color space, ascertaining extrema points for two or more two-dimensional boundaries of the plurality of two-dimensional boundaries, adjusting a color value within at least one of the two-dimensional boundaries to generate an adjusted color that reduces variances of color values for a color channel, and presenting the adjusted color on the display. By adjusting color values within human-perception limits, the number of bits used for color encoding can be reduced. ## Claims ### Claim 1 A system, for memory-efficient encoding in an extended-reality device, comprising: a display; and one or more memory devices comprising instructions that, when executed by one or more processors, causes the one or more processors to perform the following steps: calculating a plurality of two-dimensional boundaries in a color space; ascertaining extrema points for two or more two-dimensional boundaries of the plurality of two-dimensional boundaries; adjusting a color value within at least one of the two-dimensional boundaries to generate an adjusted color that reduces variances of color values for a color channel, based on ascertaining the extrema points for the two or more two-dimensional boundaries; and presenting the adjusted color on the display. ### Claim 2 (depends on 1) The system of claim 1, wherein the two-dimensional boundaries are ascertained based on human color discrimination. ### Claim 3 (depends on 1) The system of claim 1, wherein: the plurality of two-dimensional boundaries are cross sections from a plurality of color-discrimination ellipsoids; ascertaining extrema points comprises: ascertaining H and/or L for each of the plurality of the two-dimensional boundaries, where His a high value of an ellipse and L is a low value of the ellipse; and identifying a HL value and a LH value, where HL is a highest of low values L and LH is a lowest of high values H for the plurality of two-dimensional boundaries; and adjusting the color value within at least one of the two-dimensional boundaries to reduce variances of color values for the color channel is based on the HL value and/or the LH value. ### Claim 4 (depends on 3) The system of claim 3, wherein the color value in the at least one of the two-dimensional boundaries is adjusted to equal HL or LH, based on HL being greater than LH. ### Claim 5 (depends on 3) The system of claim 3, wherein each ellipsoid of the plurality of color-discrimination ellipsoids corresponds to a color for a pixel in an image. ### Claim 6 A method for memory-efficient encoding in an extended-reality device, the method comprising: calculating a plurality of two-dimensional boundaries in a color space; ascertaining extrema points for two or more two-dimensional boundaries of the plurality of two-dimensional boundaries; adjusting a color value within at least one of the two-dimensional boundaries to generate an adjusted color that reduces variances of color values for a color channel, based on ascertaining the extrema points for the two or more two-dimensional boundaries; and presenting the adjusted color on a display. ### Claim 7 (depends on 6) The method of claim 6, wherein the two-dimensional boundaries are ascertained based on human color discrimination and a function of an angle of a field of view of a person. ### Claim 8 (depends on 6) The method of claim 6, wherein: the plurality of two-dimensional boundaries are cross sections from a plurality of color-discrimination ellipsoids; ascertaining extrema points comprises: ascertaining H and/or L for each of the plurality of the two-dimensional boundaries, where His a high value of an ellipse and L is a low value of the ellipse; and identifying a HL value and a LH value, where HL is a highest of low values L and LH is a lowest of high values H for the plurality of two-dimensional boundaries; and adjusting the color value within at least one of the two-dimensional boundaries to reduce variances of color values for the color channel is based on the HL value and/or the LH value. ### Claim 9 (depends on 8) The method of claim 8, wherein the color value in the at least one of the two-dimensional boundaries is adjusted to equal HL or LH, based on HL being greater than LH. ### Claim 10 (depends on 8) The method of claim 8, wherein the color value in the at least one of the two-dimensional boundaries is adjusted to a value P, based on HL being greater than LH, wherein the value P is a value equal to or less than LH and equal to or greater than HL. ### Claim 11 (depends on 10) The method of claim 10, wherein the value P is an average of HL and LH. ### Claim 12 (depends on 8) The method of claim 8, wherein each ellipsoid of the plurality of color-discrimination ellipsoids corresponds to a color for a pixel in an image. ### Claim 13 (depends on 6) The method of claim 6, wherein the color channel is blue or red and not green. ### Claim 14 A memory device comprising instructions that, when executed by one or more processors, cause the one or more processors to perform the following steps: calculating a plurality of two-dimensional boundaries in a color space; ascertaining extrema points for two or more two-dimensional boundaries of the plurality of two-dimensional boundaries; adjusting a color value within at least one of the two-dimensional boundaries to generate an adjusted color that reduces variances of color values for a color channel, based on ascertaining extrema points for the two or more two-dimensional boundaries; and presenting the adjusted color on a display. ### Claim 15 (depends on 14) The memory device of claim 14, wherein: the plurality of two-dimensional boundaries are cross sections from a plurality of color-discrimination ellipsoids; ascertaining extrema points comprises: ascertaining H and/or L for each of the plurality of the two-dimensional boundaries, where H is a high value of an ellipse and L is a low value of the ellipse; and identifying a HL value and a LH value, where HL is a highest of low values L and LH is a lowest of high values H for the plurality of two-dimensional boundaries; and adjusting the color value within at least one of the two-dimensional boundaries to reduce variances of color values for the color channel is based on the HL value and/or the LH value. ### Claim 16 (depends on 15) The memory device of claim 15, wherein the color value in the at least one of the two-dimensional boundaries is adjusted to a value P, based on HL being greater than LH, wherein the value P is a value equal to or less than LH and equal to or greater than HL. ### Claim 17 (depends on 15) The memory device of claim 15, wherein each ellipsoid of the plurality of color-discrimination ellipsoids corresponds to a color for a pixel in an image. ### Claim 18 (depends on 14) The memory device of claim 14, wherein: the color space is a first color space; and calculating the plurality of two-dimensional boundaries comprises transforming a plurality of axis-aligned ellipsoids from a second color space into a plurality of color-discrimination ellipsoids in the first color space. ### Claim 19 (depends on 18) The memory device of claim 18, wherein: the second color space is the DKL (Derrington-Krauskopf-Lennie) space; and the first color space is the linear RGB (Red, Green, Blue) space. ### Claim 20 (depends on 14) The memory device of claim 14, wherein: the color channel is a first color channel, the instructions are configured to further cause the one or more processors to reduce variances of color values for a second color channel; and neither the first color channel nor the second color channel is green.