US5748773A
Expired / Lapsed
US
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Image processing apparatus
Assignee: Canon Inc
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Filing: 1994-11-17
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Granted: 1998-05-05
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Expires: 2014-11-17
Abstract
Abstract An image processing apparatus having a first mode for processing electrical signals by a pre-scan operation and a second mode for processing electrical signals by a main scan operation. The first mode forms a histogram on the basis of electrical signals obtained by the pre-scan operation, and detects predetermined feature points from the formed histogram. A table is formed for converting signal levels of the electrical signals according to the detected predetermined feature points of the histogram based on the image type of the original. The second mode generates reproduction signals from electrical signals obtained by the main scan operation in accordance with the table.
Inventors
- 👤 Hirohiko Tashiro
- 👤 Yoshiyuki Suzuki
- 👤 Hiroyuki Ichikawa
- 👤 Satoru Kutsuwada
- 👤 Akio Itoh
- 👤 Yoshinori Abe
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-09 12:54
CPC Classifications
G; G06; G06T; G06T5/00; G06T5/90; G06T5/92; G06T5/40; H; H04; H04N; H04N1/00; H04N1/40; H04N1/407; H04N1/4072; H04N1/4074; H04N1/4076; H04N1/4078
Claims Analysis
Total Claims: 26
Claim 1
Independent Claim
123 words
An image processing apparatus comprising: first forming means for forming a histogram on the basis of input electrical signals; detection means for detecting predetermined feature points from the formed histogram; discrimination means for discriminating an image type of an original represented by the input electrical signals according to the detected predetermined feature points; second forming means for forming a table for converting signal levels of the electrical signals according to the detected predetermined feature points based on the image type of the original discriminated by said discrimination means; and selecting means for selecting, from the feature points detected by said detection means, at least one suitable feature point for forming the table in accordance with the image type discriminated by said discrimination means.
Claim 2
Dependent Claim
123 words
An image processing apparatus comprising: first forming means for forming a histogram on the basis of input electrical signals; detection means for detecting predetermined feature points from the formed histogram; discrimination means for discriminating an image type of an original represented by the input electrical signals according to the detected predetermined feature points; second forming means for forming a table for converting signal levels of the electrical signals according to the detected predetermined feature points based on the image type of the original discriminated by said discrimination means; and selecting means for selecting, from the feature points detected by said detection means, at least one suitable feature point for forming the table in accordance with the image type discriminated by said discrimination means.
Claim 3
Dependent Claim
38 words
The apparatus according to claim 1, wherein the table formed by said second forming means is a conversion table including conversion of the electrical signals according to the image type of the original, luminance-density conversion and gradation correction.
Claim 4
Dependent Claim
43 words
The apparatus according to claim 1, wherein the predetermined feature points include lightest and darkest levels of the levels of the electrical signals, a maximum frequency of frequencies constituting the histogram, and a level of an electrical signal corresponding to the maximum frequency.
Claim 5
Dependent Claim
182 words
An image processing apparatus, which has a first mode for processing electrical signals by a prescan operation and a second mode for processing electrical signals by a main scan operation, comprising: first forming means for forming a histogram on the basis of electrical signals obtained by the prescan operation; detection means for detecting predetermined feature points from the formed histogram; discrimination means for discriminating an image type of an original represented by the input electrical signals according to the detected predetermined feature points; second forming means for forming a table for converting signal levels of the electrical signals according to the detected predetermined feature points based on the image type of the original discriminated by said discrimination means; generation means for generating reproduction signals on the basis of electrical signals obtained by the main scan operation in accordance with the table formed by said second forming means; and selecting means for selecting, from the feature points detected by said detection means, at least one suitable feature point for forming the table in accordance with the image type discriminated by said discrimination means.
Claim 6
Dependent Claim
182 words
An image processing apparatus, which has a first mode for processing electrical signals by a prescan operation and a second mode for processing electrical signals by a main scan operation, comprising: first forming means for forming a histogram on the basis of electrical signals obtained by the prescan operation; detection means for detecting predetermined feature points from the formed histogram; discrimination means for discriminating an image type of an original represented by the input electrical signals according to the detected predetermined feature points; second forming means for forming a table for converting signal levels of the electrical signals according to the detected predetermined feature points based on the image type of the original discriminated by said discrimination means; generation means for generating reproduction signals on the basis of electrical signals obtained by the main scan operation in accordance with the table formed by said second forming means; and selecting means for selecting, from the feature points detected by said detection means, at least one suitable feature point for forming the table in accordance with the image type discriminated by said discrimination means.
Claim 7
Dependent Claim
39 words
The apparatus according to claim 4, wherein the table formed by said second forming means is a conversion table including conversion of the electrical signals according to the image type of the original, luminance density conversion and gradation correction.
Claim 8
Dependent Claim
43 words
The apparatus according to claim 4, wherein the predetermined feature points include lightest and darkest levels of the levels of the electrical signals, a maximum frequency of frequencies constituting the histogram, and a level of an electrical signal corresponding to the maximum frequency.
Claim 9
Dependent Claim
181 words
An image processing apparatus, which has a first mode for processing electrical signals by a prescan operation and a second mode for processing electrical signals by a main scan operation, comprising: first forming means for forming a histogram on the basis of electrical signals obtained by the prescan operation; detection means for detecting predetermined feature points from the formed histogram; discrimination means for discriminating an image type of an original represented by the electrical signals according to the detected predetermined feature points; second forming means for forming a first table for converting luminance signals of the electrical signals according to the discriminated type of original; third forming means for forming a second table for performing luminance-density conversion of the electrical signals; generation means for generating reproduction signals from the electrical signals obtained by the main scan operation according to the formed first and second tables; and selecting means for selecting, from the feature points detected by said detection means, at least one suitable feature point for forming the first table in accordance with the image type discriminated by said discrimination means.
Claim 10
Dependent Claim
181 words
An image processing apparatus, which has a first mode for processing electrical signals by a prescan operation and a second mode for processing electrical signals by a main scan operation, comprising: first forming means for forming a histogram on the basis of electrical signals obtained by the prescan operation; detection means for detecting predetermined feature points from the formed histogram; discrimination means for discriminating an image type of an original represented by the electrical signals according to the detected predetermined feature points; second forming means for forming a first table for converting luminance signals of the electrical signals according to the discriminated type of original; third forming means for forming a second table for performing luminance-density conversion of the electrical signals; generation means for generating reproduction signals from the electrical signals obtained by the main scan operation according to the formed first and second tables; and selecting means for selecting, from the feature points detected by said detection means, at least one suitable feature point for forming the first table in accordance with the image type discriminated by said discrimination means.
Claim 11
Dependent Claim
75 words
The apparatus according to claim 7, wherein the predetermined feature points include lightest and darkest levels of the levels of the electrical signals, a maximum frequency of frequencies constituting the histogram, a level of an electrical signal corresponding to the maximum frequency, a total number of peaks, levels recognized as peaks, and a continuous amount of frequencies of a period having a largest level width of periods where frequencies exceeding a predetermined value continuously appear.
Claim 12
Dependent Claim
33 words
The apparatus according to claim 7, wherein said image processing apparatus is connected to a printing apparatus, and the second table further has a table for performing gradation correction of said printing apparatus.
Claim 13
Dependent Claim
98 words
An image processing method comprising the steps of: forming a histogram on the basis of input electrical signals; detecting predetermined feature points from the formed histogram; discriminating an image type of an original represented by the input electrical signals according to the detected predetermined feature points; and forming a table for converting signal levels of the electrical signals according to the detected predetermined feature points based on the discriminated image type of the original; and selecting, from the detected feature points, at least one suitable feature point for forming the table in accordance with the discriminated image type.
Claim 14
Dependent Claim
98 words
An image processing method comprising the steps of: forming a histogram on the basis of input electrical signals; detecting predetermined feature points from the formed histogram; discriminating an image type of an original represented by the input electrical signals according to the detected predetermined feature points; and forming a table for converting signal levels of the electrical signals according to the detected predetermined feature points based on the discriminated image type of the original; and selecting, from the detected feature points, at least one suitable feature point for forming the table in accordance with the discriminated image type.
Claim 15
Dependent Claim
147 words
An image processing method, which has a first mode for processing electrical signals by a prescan operation and a second mode for processing electrical signals by a main scan operation, comprising the steps of: forming a histogram on the basis of electrical signals obtained by the prescan operation; detecting predetermined feature points from the formed histogram; discriminating an image type of an original represented by the electrical signals according to the detected predetermined feature points; forming a table for converting signal levels of the electrical signals according to the detected predetermined feature points based on the discriminated image type of the original; generating reproduction signals on the basis of electrical signals obtained by the main scan operation in accordance with the formed table; and selecting, from the detected feature points, at least one suitable feature point for forming the table in accordance with the discriminated image type.
Claim 16
Dependent Claim
147 words
An image processing method, which has a first mode for processing electrical signals by a prescan operation and a second mode for processing electrical signals by a main scan operation, comprising the steps of: forming a histogram on the basis of electrical signals obtained by the prescan operation; detecting predetermined feature points from the formed histogram; discriminating an image type of an original represented by the electrical signals according to the detected predetermined feature points; forming a table for converting signal levels of the electrical signals according to the detected predetermined feature points based on the discriminated image type of the original; generating reproduction signals on the basis of electrical signals obtained by the main scan operation in accordance with the formed table; and selecting, from the detected feature points, at least one suitable feature point for forming the table in accordance with the discriminated image type.
Claim 17
Dependent Claim
152 words
An image processing method, which has a first mode for processing electrical signals by a prescan operation and a second mode for processing electrical signals by a main scan operation, comprising the steps of: forming a histogram on the basis of electrical signals obtained by the prescan operation; detecting predetermined feature points from the formed histogram; discriminating an image type of an original represented by the electrical signals according to the detected predetermined feature points; forming a first table for converting luminance signals of the electrical signals according to the discriminated type of original; forming a second table for performing luminance-density conversion of the electrical signals; generating reproduction signals from the electrical signals obtained by the main scan operation according to the formed first and second tables; and selecting, from the detected feature points, at least one suitable feature point for forming the first table in accordance with the discriminated image type.
Claim 18
Dependent Claim
152 words
An image processing method, which has a first mode for processing electrical signals by a prescan operation and a second mode for processing electrical signals by a main scan operation, comprising the steps of: forming a histogram on the basis of electrical signals obtained by the prescan operation; detecting predetermined feature points from the formed histogram; discriminating an image type of an original represented by the electrical signals according to the detected predetermined feature points; forming a first table for converting luminance signals of the electrical signals according to the discriminated type of original; forming a second table for performing luminance-density conversion of the electrical signals; generating reproduction signals from the electrical signals obtained by the main scan operation according to the formed first and second tables; and selecting, from the detected feature points, at least one suitable feature point for forming the first table in accordance with the discriminated image type.
Claim 19
Dependent Claim
156 words
An image processing apparatus comprising: first forming means for forming a destiny histogram on the basis of input electrical signals; first detection means for detecting predetermined feature points from the formed histogram; discrimination means for discriminating an image type of an original represented by the input electrical signals according to the detected predetermined feature points; second detection means for detecting an effective range of the density of the input electrical signals according to the detected predetermined feature points; second forming means for forming a table for converting signal levels of the electrical signals according to the detected predetermined feature points and the effective range of the density based on the image type of the original discriminated by said discrimination means; and selecting means for selecting, from the feature points detected by said first detection means, at least one suitable feature point for forming the table in accordance with the image type discriminated by said discrimination means.
Claim 20
Dependent Claim
156 words
An image processing apparatus comprising: first forming means for forming a destiny histogram on the basis of input electrical signals; first detection means for detecting predetermined feature points from the formed histogram; discrimination means for discriminating an image type of an original represented by the input electrical signals according to the detected predetermined feature points; second detection means for detecting an effective range of the density of the input electrical signals according to the detected predetermined feature points; second forming means for forming a table for converting signal levels of the electrical signals according to the detected predetermined feature points and the effective range of the density based on the image type of the original discriminated by said discrimination means; and selecting means for selecting, from the feature points detected by said first detection means, at least one suitable feature point for forming the table in accordance with the image type discriminated by said discrimination means.
Claim 21
Dependent Claim
41 words
The image processing apparatus according to claim 13, wherein said second forming means forms the table so that a converting curve of the table is substantially linear in the effective range, as an input range, detected by said second detection means.
Claim 22
Dependent Claim
47 words
The image processing apparatus according to claim 13, wherein said second detection means detects the entire input range of the density of the input electrical signals as an effective range if said discrimination means discriminates that the image type of the original is a gradation image type.
Claim 23
Dependent Claim
126 words
An image processing method comprising the steps of: forming a density histogram on the basis of input electrical signals; detecting predetermined feature points from the formed density histogram; discriminating an image type of an original represented by the input electrical signals according to the detected predetermined feature points; detecting an effective range of the density of the input electrical signals according to the detected feature points; forming a table for converting signal levels of the electrical signals according to the detected predetermined feature points and the effective range of the density on the basis of the discriminated image type of the original; and selecting, from the detected feature points, at least one suitable feature point for forming the table in accordance with the discriminated image type.
Claim 24
Dependent Claim
126 words
An image processing method comprising the steps of: forming a density histogram on the basis of input electrical signals; detecting predetermined feature points from the formed density histogram; discriminating an image type of an original represented by the input electrical signals according to the detected predetermined feature points; detecting an effective range of the density of the input electrical signals according to the detected feature points; forming a table for converting signal levels of the electrical signals according to the detected predetermined feature points and the effective range of the density on the basis of the discriminated image type of the original; and selecting, from the detected feature points, at least one suitable feature point for forming the table in accordance with the discriminated image type.
Claim 25
Dependent Claim
41 words
The image processing method according to claim 16, wherein said table is formed so that a converting curve of said table is substantially linear in the detected effective range as an input range of the density of the input electrical signals.
Claim 26
Dependent Claim
33 words
The image processing method according to claim 16, wherein the entire input range is detected as an effective range if the image type of the original is discriminated as a gradation image type.
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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) | 2001-05-04 | 2001-11-03 | 2002-05-05 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 2005-05-04 | 2005-11-03 | 2006-05-05 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2009-05-04 | 2009-11-03 | 2010-05-05 | $7700.00 | Window Closed / Lapsed |