US5596510A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Table-based linear interpolation for color correction system and method
Assignee: S TEN NINES CALIFORNIA LLC
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Filing: 1994-03-23
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Granted: 1997-01-21
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Expires: 2014-03-23
Abstract
Abstract The task of transforming a description of the color of a pixel from one color space (e.g., CMYK) to another (e.g., RGB) results from (1) obtaining a first approximation of the transformation from a base lookup table, and (2) interpolating between this first approximation and a set of neighboring approximations. The interpolation task is also carried out by a loop table, in this case a second table: the delta table. The use of lookup tables for both the first approximation and interpolation tasks produces color transformations which are extremely rapid. A simplifying assumption about the nature of the delta function, the assumption of collinearity of delta functions across broad color regions, makes it possible to use a delta table of small size.
Inventors
- 👤 Mark Boenke
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-09 12:54
CPC Classifications
H; H04; H04N; H04N1/00; H04N1/46; H04N1/56; H04N1/60; H04N1/6011; H04N1/6016; H04N1/6019
Claims Analysis
Total Claims: 8
Claim 1
Independent Claim
107 words
A computer-implemented method for transforming a first color in a first color space to a second color in a second color space different from the first color space, comprising the steps of: producing a nominal transform color from a sampled lookup table storing a plurality of transforms of a subset of preselected colors in the first color space to corresponding colors in the second color space; producing a delta value from a delta lookup table storing a plurality of interpolation values of a subset of possible colors in the second color space; and combining said nominal transform color and said delta value to create the second color.
Claim 2
Dependent Claim
107 words
A computer-implemented method for transforming a first color in a first color space to a second color in a second color space different from the first color space, comprising the steps of: producing a nominal transform color from a sampled lookup table storing a plurality of transforms of a subset of preselected colors in the first color space to corresponding colors in the second color space; producing a delta value from a delta lookup table storing a plurality of interpolation values of a subset of possible colors in the second color space; and combining said nominal transform color and said delta value to create the second color.
Claim 3
Dependent Claim
167 words
A computer-implemented method for transforming a first color in a first color space to a second color in a second color space, comprising the steps of: producing a nominal transform color, responsive to the first color, from a sampled lookup table storing preselected values representing transforms of preselected ones of a plurality of colors in the first color space into corresponding ones of a plurality of colors in the second color space; determining a region of the second color space in which said nominal transform color is located; producing a delta value, responsive to said region and a magnitude of a variation of the first color from a closest one of said preselected ones of said plurality of colors in the first color space, from a delta table storing a plurality of preselected interpolation values from the second color space, that for a particular region and a particular variation magnitude, are constant; and combining said delta value and said nominal transform color to produce the second color.
Claim 4
Dependent Claim
167 words
A computer-implemented method for transforming a first color in a first color space to a second color in a second color space, comprising the steps of: producing a nominal transform color, responsive to the first color, from a sampled lookup table storing preselected values representing transforms of preselected ones of a plurality of colors in the first color space into corresponding ones of a plurality of colors in the second color space; determining a region of the second color space in which said nominal transform color is located; producing a delta value, responsive to said region and a magnitude of a variation of the first color from a closest one of said preselected ones of said plurality of colors in the first color space, from a delta table storing a plurality of preselected interpolation values from the second color space, that for a particular region and a particular variation magnitude, are constant; and combining said delta value and said nominal transform color to produce the second color.
Claim 5
Dependent Claim
29 words
The computer implemented method of claim 2 wherein said step of determining a region includes the step of choosing from at least two regions responsive to the first color.
Claim 6
Dependent Claim
50 words
The computer implemented method of claim 2 wherein said step of producing a delta value further comprises the step of: restricting a magnitude of an interpolation value retrieved from said delta table so that when said delta value and said nominal transform color are combined, no overflow or underflow occurs.
Claim 7
Dependent Claim
136 words
A data processing apparatus for converting a first color in a first color space to a second color in a second color space, comprising: a sampled lookup table storing a plurality of transforms of a subset of preselected colors in the first color to corresponding colors in the second color space; a delta lookup table storing a plurality of interpolation values of a subset of possible colors in the second color space; and a processor for: retrieving a particular one of said plurality of transforms, responsive to a particular one of said subset of preselected colors closest to the first color, from said sampled lookup table; retrieving a particular one of said plurality of interpolation values from said delta lookup table; and combining said particular transform and said particular interpolation value to create the second color.
Claim 8
Dependent Claim
136 words
A data processing apparatus for converting a first color in a first color space to a second color in a second color space, comprising: a sampled lookup table storing a plurality of transforms of a subset of preselected colors in the first color to corresponding colors in the second color space; a delta lookup table storing a plurality of interpolation values of a subset of possible colors in the second color space; and a processor for: retrieving a particular one of said plurality of transforms, responsive to a particular one of said subset of preselected colors closest to the first color, from said sampled lookup table; retrieving a particular one of said plurality of interpolation values from said delta lookup table; and combining said particular transform and said particular interpolation value to create the second color.
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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) | 2000-01-21 | 2000-07-22 | 2001-01-21 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 2004-01-21 | 2004-07-22 | 2005-01-21 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2008-01-21 | 2008-07-22 | 2009-01-21 | $7700.00 | Window Closed / Lapsed |