IP Library › Granted Patent US 12,231,830
Granted Patent B2
US 12,231,830 · App. 17/765,317 · Granted Feb 18, 2025

System and method for analyzing surface features using a low-dimensional color space camera

Inventors: Ruikang K. Wang (Seattle, WA); Qinghua He (Seattle, WA)
Assignee: University of Washington
H04N9/67A61B5/14546A61B5/1455A61B5/443A61B5/4547A61B5/6898G06T7/0012G06T7/90H04N23/56G06T2207/10024G06T2207/10064G06T2207/30036G06T2207/30088G06T2207/30201H04N17/002
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Quick Facts
Patent No.
US 12,231,830
App. No.
17/765,317
Granted
Feb 18, 2025
Kind
B2
Abstract

In some embodiments, a computer-implemented method of generating a visualization of wavelength-dependent surface characteristics is provided. A computing device receives an input image captured by a camera, wherein the input image includes information in a low-dimensional color space. The computing device processes the input image to determine spectrum band information in a high-dimensional color space that corresponds to the input image. The computing device extracts subtractive information from the spectrum band information to obtain wavelength-dependent surface characteristic information, The computing device generates the visualization using the wavelength-dependent surface characteristic information. In some embodiments, the computing device may be a smartphone.

Claims (45)

1. A computer-implemented method of generating a visualization of wavelength-dependent surface characteristics, the method comprising:

receiving, by a computing device, an input image captured by a camera, wherein the input image includes information in a low-dimensional color space;

processing, by the computing device, the input image to determine spectrum band information in a high-dimensional color space that corresponds to the input image;

extracting, by the computing device, subtractive information representing a contribution of a background characteristic from the spectrum band information to obtain wavelength-dependent surface characteristic information representing a target characteristic; and

generating, by the computing device, the visualization using the wavelength-dependent surface characteristic information;

wherein extracting subtractive information includes:

multiplying a detected reflectance by a ratio that represents a proportion of reflectance caused by the target characteristic and the background characteristic in a first set of wavelength bands compared to a second set of wavelength bands.

2. The method of claim 1 , wherein the low-dimensional color space has three spectrum bands, and wherein the high-dimensional color space includes more than three spectrum bands.

3. The method of claim 1 , wherein processing the input image to determine spectrum band information in the high-dimensional color space that corresponds to the input image includes:

transforming the information in the low-dimensional color space into the information in the high-dimensional color space using a transformation matrix.

4. The method of claim 1 , wherein the target characteristic is melanin concentration, wherein the background characteristic is hemoglobin concentration, and wherein generating the visualization using the wavelength-dependent surface characteristic information includes generating a visualization of melanin concentration.

5. The method of claim 1 , wherein the target characteristic is hemoglobin concentration, wherein the background characteristic is melanin concentration, and wherein generating the visualization using the wavelength-dependent surface characteristic information includes generating a visualization of hemoglobin concentration.

6. The method of claim 1 , wherein the target characteristic is autofluorescence of bacteria-produced porphyrins, wherein the background characteristic is autofluorescence of facial skin or teeth, and wherein generating the visualization using the wavelength-dependent surface characteristic information includes generating a visualization of bacteria-produced porphyrins.

7. A system, comprising:

a low-dimensional color space camera;

an illumination source; and

a non-transitory computer-readable medium having computer-executable instructions stored thereon that, in response to execution by one or more processors of the system, cause the system to perform actions comprising:

receiving an input image of a target surface captured using the low-dimensional color space camera and illuminated using the illumination source;

processing the input image to determine spectrum band information in a high-dimensional color space that corresponds to the input image;

extracting subtractive information representing a contribution of a background characteristic from the spectrum band information to obtain wavelength-dependent surface characteristic information representing a target characteristic; and

generating a visualization of a wavelength-dependent surface characteristic using the wavelength-dependent surface characteristic information;

wherein extracting the subtractive information representing the contribution of the background characteristic from the spectrum band information to obtain wavelength-dependent surface characteristic information representing the target characteristic includes multiplying a detected reflectance by a ratio that represents a proportion of reflectance caused by the target characteristic and the background characteristic in a first set of wavelength bands compared to a second set of wavelength bands.

8. The system of claim 7 , further comprising a smartphone that includes at least the low-dimensional color space camera and the illumination source.

9. The system of claim 7 , wherein processing the input image to determine spectrum band information in the high-dimensional color space that corresponds to the input image includes:

transforming the input image from the low-dimensional color space to the high-dimensional color space using a transformation matrix.

10. The system of claim 7 , wherein the target characteristic is melanin concentration, wherein the background characteristic is hemoglobin concentration, and wherein generating the visualization using the wavelength-dependent surface characteristic information includes generating a visualization of melanin concentration.

11. The system of claim 7 , wherein the target characteristic is hemoglobin concentration, wherein the background characteristic is melanin concentration, and wherein generating the visualization using the wavelength-dependent surface characteristic information includes generating a visualization of hemoglobin concentration.

12. The system of claim 7 , wherein the target characteristic is autofluorescence of bacteria-produced porphyrins, wherein the background characteristic is autofluorescence of facial skin or teeth, and wherein generating the visualization using the wavelength-dependent surface characteristic information includes generating a visualization of bacteria-produced porphyrins.

13. A non-transitory computer-readable medium having computer-executable instructions stored thereon that, in response to execution by one or more processors of a computing device, cause the computing device to perform actions for generating a visualization of wavelength-dependent surface characteristics, the actions comprising:

receiving, by the computing device, an input image captured by a camera, wherein the input image includes information in a low-dimensional color space;

processing, by the computing device, the input image to determine spectrum band information in a high-dimensional color space that corresponds to the input image;

extracting, by the computing device, subtractive information representing a contribution of a background characteristic from the spectrum band information to obtain wavelength-dependent surface characteristic information representing a target characteristic; and

generating, by the computing device, the visualization using the wavelength-dependent surface characteristic information;

wherein extracting subtractive information includes multiplying a detected reflectance by a ratio that represents a proportion of reflectance caused by the target characteristic and the background characteristic in a first set of wavelength bands compared to a second set of wavelength bands.

14. The non-transitory computer-readable medium of claim 13 , wherein the target characteristic is melanin concentration, wherein the background characteristic is hemoglobin concentration, and wherein generating the visualization using the wavelength-dependent surface characteristic information includes generating a visualization of melanin concentration.

15. The non-transitory computer-readable medium of claim 13 , wherein the target characteristic is hemoglobin concentration, wherein the background characteristic is melanin concentration, and wherein generating the visualization using the wavelength-dependent surface characteristic information includes generating a visualization of hemoglobin concentration.

16. The non-transitory computer-readable medium of claim 13 , wherein the target characteristic is autofluorescence of bacteria-produced porphyrins, wherein the background characteristic is autofluorescence of facial skin or teeth, and wherein generating the visualization using the wavelength-dependent surface characteristic information includes generating a visualization of bacteria-produced porphyrins.

17. The non-transitory computer-readable medium of claim 13 , wherein processing the input image to determine spectrum band information in the high-dimensional color space that corresponds to the input image includes:

transforming the information in the low-dimensional color space into the information in the high-dimensional color space using a transformation matrix.

18. The system of claim 7 , further comprising a first device and a second device separate from the first device;

wherein the first device includes the low-dimensional color space camera and the illumination source; and

wherein the second device includes the one or more processors of the system.

19. The system of claim 7 , wherein the actions further comprise:

illuminating the target surface using the illumination source; and

capturing the input image of the target surface using the low-dimensional color space camera.

Assignments (1)
ASSIGNMENT OF ASSIGNOR'S INTEREST Recorded Jun 9, 2022
From: WANG, RUIKANG K.; HE, QINGHUA
To: UNIVERSITY OF WASHINGTON
Reel/Frame 060155/0393 →
Continuity (2)
Provisional Application 62909097 · Oct 1, 2019
Related Publication 20220329767A1 · Oct 13, 2022
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