Method and system for enhanced formulation and visualization rendering

• US 8,345,252 B2
• Filed: 03/10/2009
• Issued: 01/01/2013
• Est. Priority Date: 04/25/2005
• Status: Active Grant

• Current Assignee: X-Rite Incorporated (Danaher Corporation)
• Original Assignee: X-Rite Incorporated (Danaher Corporation)
• Inventors: Nisper, Jon Kenneth, Richardson, Thomas M., Ellens, Marc S., Huang, Changbo
• Primary Examiner(s): STOCK JR, GORDON J
• Application Number:
  US12/401,129
• Publication Number:
  US 20090213120A1
• Time in Patent Office: 1,393 Days
• Field of Search: None
• US Class Current: 356/445
• CPC Class Codes: G01J 2003/466 Coded colour; Recognition of predetermined colour; Determining proximity to predetermined colour
• CPC Class Codes: G01J 3/504 Goniometric colour measurements, for example measurements of metallic or flake based paints
• CPC Class Codes: G01J 3/51 using colour filters
• CPC Class Codes: G01N 2021/4711 Multiangle measurement
• CPC Class Codes: G01N 2021/556 Measuring separately scattering and specular
• CPC Class Codes: G01N 2021/8427 Coatings
• CPC Class Codes: G01N 21/251 Colorimeters; Construction thereof
• CPC Class Codes: G01N 21/474 Details of optical heads therefor, e.g. using optical fibres
• CPC Class Codes: G01N 21/55 Specular reflectivity
• CPC Class Codes: G01N 21/8422 Investigating thin films, e.g. matrix isolation method
• CPC Class Codes: G01N 2201/0627 Use of several LED's for spectral resolution

Abstract

An apparatus for measuring a spatially under-sampled Bidirectional Reflectance Distribution Function (BRDF) of a surface. The apparatus may comprise a first light source directed to illuminate the surface from a first illumination direction, and a plurality of sensors positioned to receive light reflected by the surface. The plurality of sensors may comprise first, second and third sensors positioned to receive light reflected by the surface in first, second and third non-coplanar directions. In various embodiments, the apparatus may also comprise a computer in communication with the plurality of sensors. The computer is configured to convert light sensed by the plurality of sensors into a first appearance property of the surface considering the first, second, and third reflectance directions.

A method of calculating xDNA, the vector sum of the observed reflectance intensity over a plurality of wavelengths and angles. Methods of using the calculated xDNA for formulating recipes for a surfaces colors. Furthermore, a method for using the calculated xDNA for rendering the surface color.

Claims

1. A method for formulating or rendering of a surface, comprising:

illuminating the surface with a first light source incident on the surface from a first illumination direction at a plurality of wavelengths;

measuring reflected light at the plurality of wavelengths in a plurality of reflectance directions, wherein the plurality of reflectance directions includes at least a first reflectance direction, a second reflectance direction and a third reflectance direction;

calculating an xDNA for the surface based on the measured reflected light, wherein the xDNA defines a weighted directional response of the surface that includes a set of vectors, and wherein each vector of the set of vectors represents a vector sum of light measured over all of the plurality of reflectance directions at a given wavelength or wavelength range; and

using the xDNA to generate a color formulation or to render the surface on a display device.

2. A method according to claim 1, wherein the measured reflected light comprise Bidirectional Reflectance Distribution Function (BRDF) data.

3. A method according to claim 1, wherein the xDNA is calculated according to the following formula:

4. A method according to claim 1, wherein use of the xDNA to generate a color formulation or to render the surface on a display device includes at least one of:

(a) accessing at least one database that contains known or reference process ranges and comparing the xDNA with the known or reference process ranges to determine a process classification;

(b) accessing at least one database that contains known or reference material characteristics and comparing the xDNA with the known or reference material characteristics to determine a material identification; and

(c) accessing at least one database that contains known or reference materials and comparing the xDNA with the known or reference materials to determine a formulation classification.

5. A method according to claim 4, wherein at least one of the process classification, material identification and formulation classification is used to calculate a shader data package for the surface being rendered.

6. A method according to claim 5, further comprising evaluating an estimated color of the rendered surface by:

rendering the estimated color of the surface;

measuring and calculating an xDNA for the estimated color of the surface;

comparing the calculated xDNA for the surface based on the measured reflected light with an observed xDNA for the estimated color of the surface;

determining at least one of an alternate process classification, an alternate material characteristic and an alternate formulation classification to minimize a difference between the observed xDNA for the estimated color of the surface and the calculated xDNA for the surface based on the measured reflected light; and

repeating the rendering, measuring and calculating, comparing, and determining steps as necessary to minimize the difference between the observed xDNA for the estimated color of the surface and the calculated xDNA for the surface based on the measured reflected light.

7. A method of processing measured color appearance into a formulation package, comprising:

measuring and calculating, using a computer, an xDNA of a surface being rendered, wherein the xDNA defines a weighted directional response of the surface that includes a set of vectors, and wherein each vector of the set of vectors represents a vector sum of light measured over all of a plurality of reflectance directions at a given wavelength or wavelength range;

accessing, using the computer, a database that includes known or reference process ranges and comparing the xDNA with the known or reference process ranges to determine a process classification;

accessing, using the computer, a database that includes known or reference material characteristics and comparing the xDNA with the known or reference material characteristics to determine a material identification;

accessing, using the computer, a database that includes known or reference materials and comparing the xDNA with the known or reference materials to determine a formulation classification;

using the process classification, material identification and formulation classification to generate a formulation package for the surface being rendered; and

implementing the formulation package to render the surface.

8. A method of developing a recipe formulation, comprising:

measuring light reflectance of a surface and calculating, using a computer, an xDNA of the surface based on the measured light reflectance, wherein the xDNA defines a weighted directional response of the surface that includes a set of vectors, and wherein each vector of the set of vectors represents a vector sum of light measured over all of a plurality of reflectance directions at a given wavelength or wavelength range;

accessing, using the computer, a database that includes known or reference material characteristics, comparing the xDNA with the known or reference material characteristic, and using the comparison in a recipe formulation engine;

accessing, using the computer, a database that includes known or reference material characteristics, comparing the xDNA with the known or reference material characteristics, and using the comparison in a process fluid dynamic engine; and

generating and implementing, using the computer, a recipe formulation from results of the recipe formulation engine and the process fluid dynamic engine.

9. A method for effectuating a visualization model, comprising:

measuring and calculating, using a computer, an xDNA of a surface, wherein the xDNA defines a weighted directional response of the surface that includes a set of vectors, and wherein each vector of the set of vectors represents a vector sum of light measured over all of a plurality of reflectance directions at a given wavelength or wavelength range;

accessing using the computer a database that includes known or reference material characteristics, comparing the xDNA with the known or reference material characteristics, and using the comparison in a recipe formulation engine;

accessing, using the computer, a database that includes known or reference material characteristics, comparing the xDNA with the known or reference material characteristics, and using the comparison in a process fluid dynamic engine; and

generating and implementing, using the computer, a visualization material model from results of the recipe formulation engine and the process fluid dynamic engine.