Patent US7280703B2 successfully refreshed from Google Patents.
US7280703B2
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Method of spatially filtering a digital image using chrominance information
Assignee: Monument Peak Ventures LLC
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Filing: 2002-11-14
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Granted: 2007-10-09
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Expires: 2022-11-14
Abstract
Abstract A method of processing a color digital image having a luminance channel and one or more chrominance channels to improve the tone scale characteristics of the image, includes the steps of: producing a control signal from the one or more chrominance channels; generating a pedestal signal containing mainly low frequency modulation by filtering the luminance channel with a spatial filter, whereby the operation of the spatial filter is modulated by the control signal; and producing a texture signal by subtracting the pedestal signal from the luminance channel.
Inventors
- 👤 Andrew C. Gallagher
- 👤 Edward B. Gindele
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-09 10:14
CPC Classifications
G; G06; G06T; G06T5/00; G06T5/73; G06T5/75; G06T5/90; G06T2207/00; G06T2207/20; G06T2207/20016; G06T2207/20048; G06T2207/20064
Claims Analysis
Total Claims: 25
Claim 1
Independent Claim
70 words
An improved method of processing a color digital image having a luminance channel and one or more chrominance channels, that includes the steps of separating the luminance channel into a first signal and a second signal, wherein the first and second signals include different spatial frequency information, wherein the improvement comprises employing one or more of the chrominance channels to separate the luminance channel into the first and second signals.
Claim 2
Dependent Claim
70 words
An improved method of processing a color digital image having a luminance channel and one or more chrominance channels, that includes the steps of separating the luminance channel into a first signal and a second signal, wherein the first and second signals include different spatial frequency information, wherein the improvement comprises employing one or more of the chrominance channels to separate the luminance channel into the first and second signals.
Claim 3
Dependent Claim
14 words
The method of claim 1 wherein the method is performed in a digital camera.
Claim 4
Dependent Claim
14 words
The method of claim 1 wherein the method is performed in a digital printer.
Claim 5
Dependent Claim
97 words
An improved method of processing a color digital image having a luminance channel and one or more chrominance channels to improve the tone scale characteristics of the image, that includes the steps of generating a pedestal signal containing mainly low frequency modulation from the luminance channel; and a texture signal by subtracting the pedestal signal from the luminance channel, modifying the pedestal signal with a tone scale function and recombining the modified pedestal signal with the texture signal to produce an enhanced luminance channel, wherein the improvement comprises employing the chrominance channels to generate the pedestal signal.
Claim 6
Dependent Claim
97 words
An improved method of processing a color digital image having a luminance channel and one or more chrominance channels to improve the tone scale characteristics of the image, that includes the steps of generating a pedestal signal containing mainly low frequency modulation from the luminance channel; and a texture signal by subtracting the pedestal signal from the luminance channel, modifying the pedestal signal with a tone scale function and recombining the modified pedestal signal with the texture signal to produce an enhanced luminance channel, wherein the improvement comprises employing the chrominance channels to generate the pedestal signal.
Claim 7
Independent Claim
79 words
A method of processing a color digital image having a luminance channel and one or more chrominance channels to improve the tone scale characteristics of the image, comprising the steps of: a) producing a control signal from the one or more chrominance channels; b) generating a pedestal signal containing mainly low frequency modulation from the luminance channel, a spatial filter, and the control signal; and c) producing a texture signal by subtracting the pedestal signal from the luminance channel.
Claim 8
Independent Claim
79 words
A method of processing a color digital image having a luminance channel and one or more chrominance channels to improve the tone scale characteristics of the image, comprising the steps of: a) producing a control signal from the one or more chrominance channels; b) generating a pedestal signal containing mainly low frequency modulation from the luminance channel, a spatial filter, and the control signal; and c) producing a texture signal by subtracting the pedestal signal from the luminance channel.
Claim 9
Independent Claim
90 words
A method of processing a color digital image having a luminance channel and one or more chrominance channels to improve the tone scale characteristics of the image, comprising the steps of: a) producing a control signal from the one or more chrominance channels; b) generating a pedestal signal containing mainly low frequency modulation by filtering the luminance channel with a spatial filter, whereby the operation of the spatial filter is modulated by the control signal; and c) producing a texture signal by subtracting the pedestal signal from the luminance channel.
Claim 10
Independent Claim
90 words
A method of processing a color digital image having a luminance channel and one or more chrominance channels to improve the tone scale characteristics of the image, comprising the steps of: a) producing a control signal from the one or more chrominance channels; b) generating a pedestal signal containing mainly low frequency modulation by filtering the luminance channel with a spatial filter, whereby the operation of the spatial filter is modulated by the control signal; and c) producing a texture signal by subtracting the pedestal signal from the luminance channel.
Claim 11
Dependent Claim
62 words
The method claimed in claim 6 , further comprising the steps of d) applying a tone scale function to the pedestal signal to produce a modified pedestal signal; e) combining the modified pedestal signal with the texture signal to produce an enhanced luminance signal; and f) combining the chrominance channel with the enhanced luminance channel to produce a processed color digital image.
Claim 12
Dependent Claim
61 words
The method claimed in claim 7 , wherein the step of producing a control signal from the one or more chrominance channels comprises the steps of: a1) calculating a gradient signal from the luminance channel; a2) determining a gradient threshold value from the chrominance channels; and a3) producing the control signal by applying the gradient threshold value to the gradient signal.
Claim 13
Dependent Claim
22 words
The method claimed in claim 8 , wherein the gradient threshold value is determined by calculating a variance of the chrominance channels.
Claim 14
Dependent Claim
30 words
The method claimed in claim 8 , wherein the gradient threshold value is determined as a function of the distance between values from the chrominance channels to a target color.
Claim 15
Dependent Claim
14 words
The method claimed in claim 10 , wherein the target color is blue sky.
Claim 16
Dependent Claim
63 words
The method claimed in claim 8 , wherein the step of generating the pedestal signal includes the steps of: b1) forming an image pyramid representation of the luminance channel having a base image and a plurality of residual images; b2) spatially filtering the base image and/or the residual images; and b3) combining the spatially filtered image pyramid representation to generate the pedestal image.
Claim 17
Dependent Claim
24 words
The method claimed in claim 8 , wherein the gradient signal is calculated from one or more low resolution versions of the luminance channel.
Claim 18
Independent Claim
147 words
A system for processing a digital image having a luminance channel and one or more chrominance channels to improve the tone scale characteristics of the image, comprising: a) means for producing a control signal from the one or more chrominance channels; b) means for generating a pedestal signal containing mainly low frequency modulation by filtering the luminance channel with a spatial filter, whereby the operation of the spatial filter is modulated by the control signal; c) means for producing a texture signal by subtracting the pedestal signal from the luminance channel; d) means for applying a tone scale function to the pedestal signal to produce a modified pedestal signal; e) means for combining the modified pedestal signal with the texture signal to produce an enhanced luminance signal; and f) means for combining the chrominance channel with the enhanced luminance channel to produce a processed color digital image.
Claim 19
Independent Claim
147 words
A system for processing a digital image having a luminance channel and one or more chrominance channels to improve the tone scale characteristics of the image, comprising: a) means for producing a control signal from the one or more chrominance channels; b) means for generating a pedestal signal containing mainly low frequency modulation by filtering the luminance channel with a spatial filter, whereby the operation of the spatial filter is modulated by the control signal; c) means for producing a texture signal by subtracting the pedestal signal from the luminance channel; d) means for applying a tone scale function to the pedestal signal to produce a modified pedestal signal; e) means for combining the modified pedestal signal with the texture signal to produce an enhanced luminance signal; and f) means for combining the chrominance channel with the enhanced luminance channel to produce a processed color digital image.
Claim 20
Dependent Claim
61 words
The method claimed in claim 14 , wherein the step of producing a control signal from the one or more chrominance channels comprises the steps of: a1) calculating a gradient signal from the luminance channel; a2) determining a gradient threshold value from the chrominance channels; and a3) producing the control signal by applying the gradient threshold value to the gradient signal.
Claim 21
Dependent Claim
32 words
The system claimed in claim 15 , wherein the means for determining a gradient threshold value employs a function of the distance between values from the chrominance channels to a target color.
Claim 22
Dependent Claim
14 words
The system claimed in claim 16 , wherein the target color is blue sky.
Claim 23
Dependent Claim
17 words
The system claimed in claim 16 , further comprising an operator interface for identifying a target color.
Claim 24
Dependent Claim
24 words
The system claimed in claim 18 , wherein the operator interface comprises a display and means for indicating a target color in the display.
Claim 25
Dependent Claim
31 words
The system claimed in claim 19 , wherein the display displays the image to be processed, and includes means for indicating a particular location in the image having the target 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) | 2010-10-08 | 2011-04-09 | 2011-10-09 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 2014-10-08 | 2015-04-09 | 2015-10-09 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2018-10-08 | 2019-04-09 | 2019-10-09 | $7700.00 | Window Closed / Lapsed |