US6546131B1
Expired / Lapsed
US
⏱️ 0.0 years remaining
Image processing method and apparatus for achieving tone reproduction suited to the image
Assignee: Canon Inc
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Filing: 1995-05-15
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Granted: 2003-04-08
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Expires: 2015-05-15
Abstract
Abstract Digital image data corresponding to an original read in by a CCD is stored in a page memory in pixel units, and a CPU reads the stored image data and creates a histogram. For an original having many high-density portions, an image is formed using a LOG conversion table which generates density data that enables reproduction of the tonality of the high-density portions. For an original which is comparatively faint, an image is formed using a LOG conversion table which generates density data that assures tone reproduction up to the maximum density of the original even if high-density portions cannot be reproduced. As a result, tone reproduction suited to the original image can be realized at all times.
Inventors
- 👤 Yoshito Mizoguchi
- 👤 Sono Gu
- 👤 Satoru Fukushima
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-09 09:41
CPC Classifications
H; H04; H04N; H04N1/00; H04N1/46; H04N1/56; H04N1/60; H04N1/6027; H04N1/40; H04N1/407; H04N1/4072; H04N1/4074
Claims Analysis
Total Claims: 16
Claim 1
Independent Claim
126 words
A color-image processing apparatus for converting luminance information based upon an original image into density information and outputting the density information, comprising: scanning means for scanning the original image and generating luminance information including a plurality of color component data; detecting means for detecting a distribution of each of the color component data which is obtained during a first scanning of said scanning means; setting means for setting a conversion condition, being common to the plurality of color component data, based upon a color distribution of each of the color component data detected by said detecting means; and converting means for converting the luminance information, which is obtained during a second scanning of said scanning means, into the density information in accordance with the conversion condition.
Claim 2
Dependent Claim
126 words
A color-image processing apparatus for converting luminance information based upon an original image into density information and outputting the density information, comprising: scanning means for scanning the original image and generating luminance information including a plurality of color component data; detecting means for detecting a distribution of each of the color component data which is obtained during a first scanning of said scanning means; setting means for setting a conversion condition, being common to the plurality of color component data, based upon a color distribution of each of the color component data detected by said detecting means; and converting means for converting the luminance information, which is obtained during a second scanning of said scanning means, into the density information in accordance with the conversion condition.
Claim 3
Dependent Claim
25 words
The apparatus according to claim 1 , wherein the distribution of the luminance information is obtained by extracting a frequency of a high-density level range.
Claim 4
Dependent Claim
22 words
The apparatus according to claim 1 , wherein said detecting means includes a counter for accumulating a frequency of a predetermined density.
Claim 5
Dependent Claim
47 words
The apparatus according to claim 1 , further comprising: memory means for storing processing coefficients for performing a conversion by said converting means; and control means for selecting and controlling the processing coefficients stored in said memory means in accordance with the distribution of the luminance information.
Claim 6
Dependent Claim
89 words
A color-image processing method comprising the steps of: scanning an original image and generating first luminance information including a plurality of color component data; detecting a distribution of each of the color component data; scanning the original image and generating second luminance information; setting a conversion condition, being common to the plurality of color component data, based upon a color distribution of each of the color component data detected at said detecting step; and converting the second luminance information into the density information in accordance with the conversion condition.
Claim 7
Dependent Claim
89 words
A color-image processing method comprising the steps of: scanning an original image and generating first luminance information including a plurality of color component data; detecting a distribution of each of the color component data; scanning the original image and generating second luminance information; setting a conversion condition, being common to the plurality of color component data, based upon a color distribution of each of the color component data detected at said detecting step; and converting the second luminance information into the density information in accordance with the conversion condition.
Claim 8
Dependent Claim
85 words
A color-image processing apparatus comprising: storage means for storing plural color correction conditions suitable for a predetermined color; input means for inputting a plurality of color component signals representing a color original; detecting means for detecting a distribution of the color original; selecting means for selecting a color correction condition according to the detected distribution from among color correction conditions stored in said storage means; and correcting means for correcting the color component signals representing the color original based upon the selected color correction condition.
Claim 9
Dependent Claim
85 words
A color-image processing apparatus comprising: storage means for storing plural color correction conditions suitable for a predetermined color; input means for inputting a plurality of color component signals representing a color original; detecting means for detecting a distribution of the color original; selecting means for selecting a color correction condition according to the detected distribution from among color correction conditions stored in said storage means; and correcting means for correcting the color component signals representing the color original based upon the selected color correction condition.
Claim 10
Dependent Claim
15 words
The apparatus according to claim 6 , wherein the color correction conditions are matrix coefficients.
Claim 11
Dependent Claim
45 words
The apparatus according to claim 6 , wherein said detecting means detects a color having a large distribution in the color original as a representative color in the predetermined color, and said selecting means selects a color correction condition corresponding to the detected representative color.
Claim 12
Dependent Claim
62 words
The apparatus according to claim 6 , wherein said storing means stores a color correction condition which is obtained such that an average of reproducibility errors of each of the plurality of different colors is minimized, and said selecting means selects the color correction condition in a case where said detecting means detects that various colors are included in siad color original.
Claim 13
Dependent Claim
20 words
The apparatus according to claim 6 , further comprising image forming means for forming an image based on density information.
Claim 14
Dependent Claim
23 words
The apparatus according to claim 6 , further comprising image forming means for forming an image based on the corrected color component signals.
Claim 15
Dependent Claim
77 words
The color-image processing method comprising the steps of: storing plural color correction conditions suitable for a predetermined color in a storage means; inputting a plurality of color component signals representing a color original; detecting a distribution of the color original; selecting a color correction condition according to the detected distribution from among color correction conditions stored in said storage means; and correcting the color component signals representing the color original based upon the selected color correction condition.
Claim 16
Dependent Claim
77 words
The color-image processing method comprising the steps of: storing plural color correction conditions suitable for a predetermined color in a storage means; inputting a plurality of color component signals representing a color original; detecting a distribution of the color original; selecting a color correction condition according to the detected distribution from among color correction conditions stored in said storage means; and correcting the color component signals representing the color original based upon the selected color correction condition.
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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) | 2006-04-07 | 2006-10-07 | 2007-04-08 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 2010-04-07 | 2010-10-07 | 2011-04-08 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2014-04-07 | 2014-10-07 | 2015-04-08 | $7700.00 | Window Closed / Lapsed |