US7965418B2
Active / In Force
US
⏱️ 4.0 years remaining
Image processing apparatus and image processing method
Assignee: Canon Inc
•
Filing: 2010-11-23
•
Granted: 2011-06-21
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Expires: 2030-11-23
Abstract
Abstract Image processing apparatus and image processing method for formation of high quality image by high-speed error diffusion processing by execution of more complicated threshold condition processing in a simple manner. When error diffusion processing is performed on multivalued image data having plural density components and the result of processing is outputted, upon execution of error diffusion processing on a first density component among the plural density components, a threshold value used in the error diffusion processing is determined based on a density value of a second density component, then the error diffusion processing is performed on the first density component based on the determined threshold value, and the result of execution of the error diffusion processing is outputted. Further, upon execution of the error diffusion processing on the second density component among the plural density components, a threshold value used in the error diffusion processing is determined based on a density value of the first density component, then the error diffusion processing is performed on the second density component based on the determined threshold value, and the result of the error diffusion processing is outputted.
Inventors
- 👤 Akitoshi Yamada
- 👤 Hiromitsu Hirabayashi
- 👤 Masao Kato
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-09 11:55
CPC Classifications
H; H04; H04N; H04N1/00; H04N1/46; H04N1/52
Claims Analysis
Total Claims: 11
Claim 1
Independent Claim
215 words
An image processing apparatus for performing error diffusion processing on multivalued image data comprised of plural density data and outputting a result of the error diffusion processing, comprising: a first determination unit configured to, upon performing error diffusion processing on a first density data of the plural density data, determine a threshold value used for the error diffusion processing on the first density data, based on a second density data of the plural density data; a first error diffusion unit configured to perform the error diffusion processing on the first density data, based on the threshold value determined by said first determination unit; a first output unit configured to output a result of the error diffusion processing performed by said first error diffusion unit; a second determination unit configured to, upon performing error diffusion processing on the second density data, determine a threshold value used for the error diffusion processing on the second density data, based on a density value of the first density data; a second error diffusion unit configured to perform the error diffusion processing on the second density data, based on the threshold value determined by said second determination unit; and a second output unit configured to output a result of the error diffusion processing performed by said second error diffusion unit.
Claim 2
Dependent Claim
215 words
An image processing apparatus for performing error diffusion processing on multivalued image data comprised of plural density data and outputting a result of the error diffusion processing, comprising: a first determination unit configured to, upon performing error diffusion processing on a first density data of the plural density data, determine a threshold value used for the error diffusion processing on the first density data, based on a second density data of the plural density data; a first error diffusion unit configured to perform the error diffusion processing on the first density data, based on the threshold value determined by said first determination unit; a first output unit configured to output a result of the error diffusion processing performed by said first error diffusion unit; a second determination unit configured to, upon performing error diffusion processing on the second density data, determine a threshold value used for the error diffusion processing on the second density data, based on a density value of the first density data; a second error diffusion unit configured to perform the error diffusion processing on the second density data, based on the threshold value determined by said second determination unit; and a second output unit configured to output a result of the error diffusion processing performed by said second error diffusion unit.
Claim 3
Dependent Claim
33 words
The apparatus according to claim 1 , wherein said first and second determination units use, for determining the respective threshold values, a table for defining a relationship between threshold values and density values.
Claim 4
Dependent Claim
19 words
The apparatus according to claim 1 , wherein said first and second determination units respectively determine plural threshold values.
Claim 5
Dependent Claim
36 words
The apparatus according to claim 3 , wherein said first and second determination units respectively use, for determining each of the plural threshold values, plural tables each for defining a relationship between thresholds and density values.
Claim 6
Dependent Claim
53 words
The apparatus according to claim 1 , wherein the plural density data are a yellow component, a magenta component, a cyan component and a black component, and the first density data is the cyan component, and the second density data is the magenta component, and a third color component is the black component.
Claim 7
Dependent Claim
36 words
The apparatus according to claim 1 , further comprising an image formation unit configured to input the results of the error diffusion processing performed by said first and second error diffusion units, and form an image.
Claim 8
Dependent Claim
16 words
The apparatus according to claim 6 , wherein said image formation unit is an ink-jet printer.
Claim 9
Dependent Claim
208 words
An image processing method for performing error diffusion processing on multivalued image data comprised of plural density data and outputting a result of the error diffusion processing, comprising: a first determination step of, upon performing error diffusion processing on a first density data of the plural density data, determining a threshold value used for the error diffusion processing on the first density data, based on a second density data of the plural density data; a first error diffusion step of performing the error diffusion processing on the first density data, based on the threshold value determined at said first determination step; a first output step of outputting a result of the error diffusion processing performed at said first error diffusion step; a second determination step of, upon performing error diffusion processing on the second density data, determining a threshold value used for the error diffusion processing on the second density data, based on density value of the first density data; a second error diffusion step of performing the error diffusion processing on the second density data, based on the threshold value determined at said second determination step; and a second output step of outputting a result of the error diffusion processing performed at said second error diffusion step.
Claim 10
Dependent Claim
208 words
An image processing method for performing error diffusion processing on multivalued image data comprised of plural density data and outputting a result of the error diffusion processing, comprising: a first determination step of, upon performing error diffusion processing on a first density data of the plural density data, determining a threshold value used for the error diffusion processing on the first density data, based on a second density data of the plural density data; a first error diffusion step of performing the error diffusion processing on the first density data, based on the threshold value determined at said first determination step; a first output step of outputting a result of the error diffusion processing performed at said first error diffusion step; a second determination step of, upon performing error diffusion processing on the second density data, determining a threshold value used for the error diffusion processing on the second density data, based on density value of the first density data; a second error diffusion step of performing the error diffusion processing on the second density data, based on the threshold value determined at said second determination step; and a second output step of outputting a result of the error diffusion processing performed at said second error diffusion step.
Claim 11
Dependent Claim
22 words
A non-transitory computer readable memory for storing a program for executing an image processing method according to claim 8 in a computer.
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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) | 2014-06-20 | 2014-12-20 | 2015-06-21 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 2018-06-20 | 2018-12-20 | 2019-06-21 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2022-06-20 | 2022-12-20 | 2023-06-21 | $7700.00 | Window Closed / Lapsed |