System and method for establishing an aggregate degree of brightness for each primary color to create a composite color digital image

• US 6,785,414 B1
• Filed: 09/28/2000
• Issued: 08/31/2004
• Est. Priority Date: 09/28/2000
• Status: Expired due to Term

• Current Assignee: Media Cybernetics, Inc. (Roper Technologies, Inc.)
• Original Assignee: Media Cybernetics, Inc. (Roper Technologies, Inc.)
• Inventors: Ryan, Kevin W., Marek, Louis F. Jr., McStravick, Arnold W. III
• Primary Examiner(s): Wu, Jingge
• Application Number:
  US09/671,113
• Time in Patent Office: 1,433 Days
• Field of Search: 348/360-371, 355/68-77, 382/162-180, 396/231-242, 358/518-523
• US Class Current: 382/162
• CPC Class Codes: G06T 11/001 Texturing; Colouring; Generation of texture or colour inpainting G06T5/77
• CPC Class Codes: H04N 23/73 by influencing the exposure time

Abstract

A system and method for establishing an aggregate degree of brightness for each primary color to create a composite color digital image. One of a plurality of primary colors is selected. A color digital image is captured with a color digital camera. The aggregate degree of brightness for the selected primary color is determined. The determined aggregate degree of brightness for the selected primary color is compared with the desired degree of brightness for the selected primary color. If the determined aggregate degree of brightness is not within a tolerance band surrounding the desired degree of brightness, then an adjustment is made to an exposure time controller of the color digital camera. This process is repeated until the determined aggregate degree of brightness is within the tolerance band surrounding the desired degree of brightness. If the determined aggregate degree of brightness is within the tolerance band surrounding the desired degree of brightness, then photosite values for the selected primary color are copied into corresponding pixels in a buffer. The process is repeated for each remaining primary color.

Claims

1. A method for creating a composite color digital image wherein, for each primary color, an aggregate degree of brightness can be set within a tolerance band surrounding a desired aggregate degree of brightness, comprising:

(a) selecting one of a plurality of primary colors;

(b) capturing a color digital image with a color digital camera;

(c) determining the aggregate degree of brightness for the selected one of the plurality of primary colors in the color digital image;

(d) copying photosite values, for the selected one of the plurality of primary colors, into corresponding pixels in a buffer; and

(e) repeating the method for each remaining primary color, thereby creating the composite color digital image wherein, for each primary color, the aggregate degree of brightness is within the tolerance band surrounding the desired aggregate degree of brightness.

2. The method according to claim 1, wherein said determining further comprises:

(a) preparing, from the color digital image, a histogram for the selected one of the plurality of primary colors; and

(b) determining, from the histogram, the aggregate degree of brightness for the selected one of the plurality of primary colors.

3. The method according to claim 1, further comprising, between said determining and said copying:

(a) comparing said determined aggregate degree of brightness, for the selected one of the plurality of primary colors, with the desired aggregate degree of brightness for the selected one of the plurality of primary colors;

(b) adjusting an exposure time controller of the color digital camera if a result of said comparing reveals that said determined aggregate degree of brightness, for the selected one of the plurality of primary colors, is not within the tolerance band surrounding the desired aggregate degree of brightness, for the selected one of the plurality of primary colors; and

(c) reiterating said capturing, said determining, said comparing, and said adjusting if the result of said comparing reveals that said determined aggregate degree of brightness, for the selected one of the plurality of primary colors, is not within the tolerance band surrounding the desired aggregate degree of brightness, for the selected one of the plurality of primary colors.

4. The method according to claim 3, wherein, if the result of said comparing reveals that said determined aggregate degree of brightness, for the selected one of the plurality of primary colors, is greater than an upper value of the tolerance band surrounding the desired aggregate degree of brightness, for the selected one of the plurality of primary colors, said adjusting further comprises setting the exposure time controller so as to decrease an exposure time of the color digital camera.

5. The method according to claim 3, wherein, if the result of said comparing reveals that said determined aggregate degree of brightness, for the selected one of the plurality of primary colors, is less than a lower value of the tolerance band surrounding the desired aggregate degree of brightness, for the selected one of the plurality of primary colors, said adjusting further comprises setting the exposure time controller so as to increase an exposure time of the color digital camera.

6. The method according to claim 1, wherein the color digital camera has a single image sensor.

7. The method according to claim 1, wherein the color digital camera has a plurality of image sensors.

8. The method according to claim 1, wherein an image sensor, of the color digital camera, uses a charge-coupled device technology.

9. The method according to claim 1, wherein an image sensor, of the color digital camera, uses a complementary metal oxide semiconductor technology.

10. The method according to claim 1, wherein a color filter, of the color digital camera, is a pattern of individual filters, each of the individual filters affixed to and covering a photosite on an image sensor.

11. The method according to claim 10, wherein the pattern of individual filters is a Bayer mosaic filter.

12. The method according to claim 1, wherein a color filter, of the color digital camera, is a collection of individual filters such that each of the individual filters is capable of covering an image sensor.

13. The method according to claim 1, wherein a color filter, of the color digital camera, is a composite filter unit that can be controlled to filter different colors and that is capable of covering an image sensor.

14. The method according to claim 13, wherein the composite filter unit uses a liquid crystal display technology.

15. A system for creating a composite color digital image using a color digital camera, comprising:

a controller to set a desired aggregate degree of brightness for at least one of a plurality of primary colors;

one or more color filters to filter an image according to each of said primary colors; and

a buffer to store photosite values for each of said primary colors into corresponding pixels of said buffer, thereby creating the composite color digital image.

16. The system according to claim 15, wherein said controller manually sets the desired aggregate degree of brightness for at least one of said plurality of primary colors.

17. The system according to claim 15, wherein said controller automatically sets the desired aggregate degree of brightness for at least one of said plurality of primary colors.

18. The system according to claim 15, wherein the color digital camera uses an exposure time controller to control exposure time.

19. The system according to claim 18, wherein said controller adjusts said exposure time controller.

20. The system according to claim 19, wherein said controller further comprises:

a histogram function module to prepare a histogram of said photosite values for each of said primary colors;

a calculator to determine an aggregate degree of brightness for each of said primary colors; and

a comparer to compare said determined aggregate degree of brightness for each of said primary colors with a corresponding said desired aggregate degree of brightness for each of said primary colors.

21. The system according to claim 20, wherein said comparer receives, manually or automatically, said desired aggregate degree of brightness for each of said primary colors and a corresponding tolerance band for each of said primary colors.

22. The system according to claim 20, wherein said controller further comprises a photosite identifier to identify which photosites on one or more image sensors correspond to each of said primary colors.

23. The system according to claim 15, wherein the color digital camera has a single image sensor.

24. The system according to claim 15, wherein the color digital camera has a plurality of image sensors.

25. The system according to claim 15, wherein the color filter is a pattern of individual filters, each of the individual filters affixed to and covering a photosite on an image sensor.

26. The system according to claim 25, wherein the pattern of individual filters is a Bayer mosaic filter.

27. The system according to claim 15, wherein the color filter is a collection of individual filters such that each of the individual filters is capable of covering an image sensor.

28. The system according to claim 15, wherein the color filter is a composite filter unit that can be controlled to filter different colors and that is capable of covering an image sensor.

29. The system according to claim 28, wherein the composite filter unit uses a liquid crystal display technology.