Patent US6771815B2 successfully refreshed from Google Patents.
US6771815B2
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Image correction apparatus and recording medium for storing image correction program
Assignee: Nikon Corp
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Filing: 2000-02-18
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Granted: 2004-08-03
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Expires: 2020-02-18
Abstract
Abstract A histogram is prepared by calculating the pixel number ratio corresponding to each gradation in relation to the total number of pixels in image data obtained from the outside. A threshold value for the pixel number ratio corresponding to a given gradation that is determined through user specification is compared against the pixel number ratio corresponding to each gradation in the histogram. Based upon the results of the comparison, the histogram gradation width is corrected. For instance, the width representing the range of gradations with pixel number ratios smaller than the threshold value in the histogram is compressed. Then, the gradation width in the histogram is expanded to achieve the number of pre-compression gradations.
Inventors
- 👤 Juping Yang
- 👤 Yukio Nakagawa
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-09 10:24
CPC Classifications
G; G06; G06T; G06T5/00; G06T5/40; G06T5/90; G06T5/92
Claims Analysis
Total Claims: 12
Claim 1
Independent Claim
131 words
An image correction apparatus, comprising: an image intake unit that obtains image data from outside; a histogram preparation unit that prepares a histogram by calculating a pixel number ratio at each gradation against the total number of pixels based upon the image data; and a gradation correction unit that corrects a gradation width in said histogram based upon a comparison of a threshold value for said pixel number ratio at a gradation and the pixel number ratio at each gradation in said histogram, said threshold value being determined through user specification, wherein: said gradation correction unit compresses a width corresponding to a range of gradations having pixel number ratios smaller than said threshold value in said histogram at a compression rate that is in inverse proportion to said pixel number ratio.
Claim 2
Dependent Claim
131 words
An image correction apparatus, comprising: an image intake unit that obtains image data from outside; a histogram preparation unit that prepares a histogram by calculating a pixel number ratio at each gradation against the total number of pixels based upon the image data; and a gradation correction unit that corrects a gradation width in said histogram based upon a comparison of a threshold value for said pixel number ratio at a gradation and the pixel number ratio at each gradation in said histogram, said threshold value being determined through user specification, wherein: said gradation correction unit compresses a width corresponding to a range of gradations having pixel number ratios smaller than said threshold value in said histogram at a compression rate that is in inverse proportion to said pixel number ratio.
Claim 3
Dependent Claim
124 words
An image correction apparatus, comprising: an image intake unit that obtains image data from outside; a histogram preparation unit that prepares a histogram by calculating a pixel number ratio at each gradation against the total number of pixels based upon the image data; and a gradation correction unit that corrects a gradation width in said histogram based upon a comparison of a threshold value for said pixel number ratio at a gradation and the pixel number ratio at each gradation in said histogram, said threshold value being determined through user specification, wherein: said gradation correction unit compresses a width corresponding to a range of gradations having pixel number ratios smaller than said threshold value in said histogram to a minimum gradation width of 1.
Claim 4
Dependent Claim
124 words
An image correction apparatus, comprising: an image intake unit that obtains image data from outside; a histogram preparation unit that prepares a histogram by calculating a pixel number ratio at each gradation against the total number of pixels based upon the image data; and a gradation correction unit that corrects a gradation width in said histogram based upon a comparison of a threshold value for said pixel number ratio at a gradation and the pixel number ratio at each gradation in said histogram, said threshold value being determined through user specification, wherein: said gradation correction unit compresses a width corresponding to a range of gradations having pixel number ratios smaller than said threshold value in said histogram to a minimum gradation width of 1.
Claim 5
Dependent Claim
120 words
An image correction apparatus, comprising: an image intake unit that obtains image data from outside; a histogram preparation unit that prepares a histogram by calculating a pixel number ratio at each gradation against the total number of pixels based upon the image data; and a gradation correction unit that corrects a gradation width in said histogram based upon a comparison of a threshold value for said pixel number ratio at a gradation and the pixel number ratio at each gradation in said histogram, said threshold value being determined through user specification and being expressed as a function (S(i)) of a gradation (i), wherein: said threshold value (S(i)) and the pixel number ratio are compared for each gradation in said histogram.
Claim 6
Dependent Claim
120 words
An image correction apparatus, comprising: an image intake unit that obtains image data from outside; a histogram preparation unit that prepares a histogram by calculating a pixel number ratio at each gradation against the total number of pixels based upon the image data; and a gradation correction unit that corrects a gradation width in said histogram based upon a comparison of a threshold value for said pixel number ratio at a gradation and the pixel number ratio at each gradation in said histogram, said threshold value being determined through user specification and being expressed as a function (S(i)) of a gradation (i), wherein: said threshold value (S(i)) and the pixel number ratio are compared for each gradation in said histogram.
Claim 7
Dependent Claim
149 words
A recording medium that stores an image correction program and can be read, said image correction program comprising: an image intake procedure in which image data are obtained from outside; a histogram preparation procedure in which a histogram is prepared by calculating a pixel number ratio of each gradation against a total number of pixels based upon said image data; and a gradation correction procedure in which a histogram gradation width is corrected based upon comparison of a threshold value for said pixel number ratio at a gradation and said pixel number ratio corresponding to each gradation in said histogram, said threshold value being determined through user specification, wherein: in said gradation correction procedure, a width corresponding to a range of gradations with pixel number ratios smaller than said threshold value in said histogram is compressed at compression ratio that is in inverse proportion to said pixel number ratio.
Claim 8
Dependent Claim
149 words
A recording medium that stores an image correction program and can be read, said image correction program comprising: an image intake procedure in which image data are obtained from outside; a histogram preparation procedure in which a histogram is prepared by calculating a pixel number ratio of each gradation against a total number of pixels based upon said image data; and a gradation correction procedure in which a histogram gradation width is corrected based upon comparison of a threshold value for said pixel number ratio at a gradation and said pixel number ratio corresponding to each gradation in said histogram, said threshold value being determined through user specification, wherein: in said gradation correction procedure, a width corresponding to a range of gradations with pixel number ratios smaller than said threshold value in said histogram is compressed at compression ratio that is in inverse proportion to said pixel number ratio.
Claim 9
Dependent Claim
141 words
A recording medium that stores an image correction program and can be read, said image correction program comprising: an image intake procedure in which image data are obtained from outside; a histogram preparation procedure in which a histogram is prepared by calculating a pixel number ratio of each gradation against a total number of pixels based upon said image data; and a gradation correction procedure in which a histogram gradation width is corrected based upon comparison of a threshold value for said pixel number ratio at a gradation and said pixel number ratio corresponding to each gradation in said histogram, said threshold value being determined through user specification, wherein: in said gradation correction procedure, said width corresponding to a range of gradations having the pixel number ratios smaller than said threshold value is compressed to a minimum gradation width of 1.
Claim 10
Dependent Claim
141 words
A recording medium that stores an image correction program and can be read, said image correction program comprising: an image intake procedure in which image data are obtained from outside; a histogram preparation procedure in which a histogram is prepared by calculating a pixel number ratio of each gradation against a total number of pixels based upon said image data; and a gradation correction procedure in which a histogram gradation width is corrected based upon comparison of a threshold value for said pixel number ratio at a gradation and said pixel number ratio corresponding to each gradation in said histogram, said threshold value being determined through user specification, wherein: in said gradation correction procedure, said width corresponding to a range of gradations having the pixel number ratios smaller than said threshold value is compressed to a minimum gradation width of 1.
Claim 11
Dependent Claim
140 words
A recording medium that stores an image correction program and can be read, said image correction program comprising: an image intake procedure in which image data are obtained from outside; a histogram preparation procedure in which a histogram is prepared by calculating a pixel number ratio of each gradation against a total number of pixels based upon said image data; and a gradation correction procedure in which a histogram gradation width is corrected based upon comparison of a threshold value for said pixel number ratio at a gradation and said pixel number ratio corresponding to each gradation in said histogram, said threshold value being determined through user specification, wherein: said threshold value is expressed as a function (S(i)) of a gradation (i) and the threshold value S(i) and the pixel number ratio are compared for each gradation in said histogram.
Claim 12
Dependent Claim
140 words
A recording medium that stores an image correction program and can be read, said image correction program comprising: an image intake procedure in which image data are obtained from outside; a histogram preparation procedure in which a histogram is prepared by calculating a pixel number ratio of each gradation against a total number of pixels based upon said image data; and a gradation correction procedure in which a histogram gradation width is corrected based upon comparison of a threshold value for said pixel number ratio at a gradation and said pixel number ratio corresponding to each gradation in said histogram, said threshold value being determined through user specification, wherein: said threshold value is expressed as a function (S(i)) of a gradation (i) and the threshold value S(i) and the pixel number ratio are compared for each gradation in said histogram.
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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) | 2007-08-03 | 2008-02-02 | 2008-08-03 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 2011-08-03 | 2012-02-02 | 2012-08-03 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2015-08-03 | 2016-02-02 | 2016-08-03 | $7700.00 | Window Closed / Lapsed |