US5487020A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Refinement of color images using reference colors
Assignee: Canon Inc
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Filing: 1994-01-12
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Granted: 1996-01-23
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Expires: 2014-01-12
Abstract
Abstract Methods of correcting color images often involve a complex interrelation of many color components and require extensive training to be able to be fully utilized. The present disclosure involves a simplified form of color correction. From the selection of a series of actual (16,17) and desired (18,19) colors, a series of contrast and brightness values are derived, which can then be applied to the color image to produce the color corrected image.
Inventors
- 👤 Timothy Long
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-23 18:31
CPC Classifications
G; G03; G03F; G03F3/00; G03F3/10; G03F3/101; H; H04; H04N; H04N1/00; H04N1/46; H04N1/56; H04N1/60; H04N1/62; H04N1/622; H04N9/00; H04N9/64; H04N9/646
Claims Analysis
Total Claims: 4
Claim 1
Independent Claim
128 words
A method for color correcting a predetermined portion of a color image, said color image comprising a plurality of pixels and a plurality of color information channels for each of said plurality of pixels, said method comprising the steps of: selecting in said predetermined portion a first input reference color of a first pixel and a corresponding first desired output color of the first pixel; selecting in said predetermined portion a second input reference color of a second pixel and a corresponding second desired output color of the second pixel; defining a linear color transformation for each color information channel based on the input reference colors and the desired output colors; applying said linear color transformation to all pixels in said predetermined portion; and displaying the color image.
Claim 2
Independent Claim
128 words
A method for color correcting a predetermined portion of a color image, said color image comprising a plurality of pixels and a plurality of color information channels for each of said plurality of pixels, said method comprising the steps of: selecting in said predetermined portion a first input reference color of a first pixel and a corresponding first desired output color of the first pixel; selecting in said predetermined portion a second input reference color of a second pixel and a corresponding second desired output color of the second pixel; defining a linear color transformation for each color information channel based on the input reference colors and the desired output colors; applying said linear color transformation to all pixels in said predetermined portion; and displaying the color image.
Claim 3
Dependent Claim
32 words
A method of correcting a color image as claimed in claim 1 wherein said linear color transformation includes contrast and brightness values for each said color information channel of said color image.
Claim 4
Dependent Claim
26 words
A method of correcting a color image as claimed in claim 1 wherein said plurality of color information channels include red, green and blue color channels.
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USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1999-01-22 | 1999-07-24 | 2000-01-23 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 2003-01-22 | 2003-07-24 | 2004-01-23 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2007-01-22 | 2007-07-24 | 2008-01-23 | $7700.00 | Window Closed / Lapsed |