Patent US5790699A successfully refreshed from Google Patents.
US5790699A
Expired / Lapsed
US
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Macrodetector based image conversion system
Assignee: Xerox Corp
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Filing: 1995-10-27
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Granted: 1998-08-04
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Expires: 2015-10-27
Abstract
Abstract An image detection and pixel processing system includes a plurality of detector elements for receiving an image. The detector elements are subdivided into a plurality of macrodetectors, with each macrodetector constituting four or more detector elements, and with each macrodetector providing information for determining both a total light intensity value within the macrodetector and a centroid of light intensity indicative of light intensity position within the macrodetector. An image processing assembly receives information from the plurality of macrodetectors, with the image processing assembly relating a pixel and its encompassed subpixel area to each corresponding macrodetector, and further determining the total light intensity within the pixel and the centroid of light intensity within the subpixel. The image processing assembly is capable of rendering each subpixel area as an edge when magnitude of the centroid of light intensity is greater than a predetermined threshold.
Inventors
- 👤 Warren B. Jackson
- 👤 David A. Jared
- 👤 Sumit Basu
- 👤 David K. Biegelsen
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-09 10:50
CPC Classifications
H; H04; H04N; H04N1/00; H04N1/40; H04N1/409; H04N1/4092
Claims Analysis
Total Claims: 13
Claim 1
Independent Claim
205 words
An image detection and pixel processing system comprising a plurality of macrodetector elements for receiving an image, the plurality of macrodetector elements subdivided into a plurality of detector elements, with each macrodetector constituting four or more detector elements, and with each macrodetector providing information for determining both a total light intensity value within the macrodetector and a centroid of light intensity indicative of light intensity position within the macrodetector, and an image processing assembly connected to receive information from the plurality of macrodetectors, the image processing assembly relating a pixel and its encompassed subpixel area to each corresponding macrodetector, and further determining the total light intensity within the pixel and the centroid of light intensity within the subpixel area with the image processing assembly rendering each subpixel area as an edge when magnitude of the centroid of light intensity is greater than a predetermined threshold, and wherein the image processing assembly renders the subpixel area as an edge by finding a first gray value on a first side of the edge, determining actual edge position, and using actual edge position and the first gray value to determine a second gray value on a second side of the edge opposite the first side of the edge.
Claim 2
Dependent Claim
205 words
An image detection and pixel processing system comprising a plurality of macrodetector elements for receiving an image, the plurality of macrodetector elements subdivided into a plurality of detector elements, with each macrodetector constituting four or more detector elements, and with each macrodetector providing information for determining both a total light intensity value within the macrodetector and a centroid of light intensity indicative of light intensity position within the macrodetector, and an image processing assembly connected to receive information from the plurality of macrodetectors, the image processing assembly relating a pixel and its encompassed subpixel area to each corresponding macrodetector, and further determining the total light intensity within the pixel and the centroid of light intensity within the subpixel area with the image processing assembly rendering each subpixel area as an edge when magnitude of the centroid of light intensity is greater than a predetermined threshold, and wherein the image processing assembly renders the subpixel area as an edge by finding a first gray value on a first side of the edge, determining actual edge position, and using actual edge position and the first gray value to determine a second gray value on a second side of the edge opposite the first side of the edge.
Claim 3
Dependent Claim
37 words
The image detection and pixel processing system of claim 1, wherein determining actual edge position further comprises partially determining parameterization of the edge using gray-on-gray moments, and converting gray-on-gray moments to gray-on-black to uniquely define edge location.
Claim 4
Dependent Claim
40 words
The image detection and pixel processing system of claim 2, wherein partially determining parameterization of the edge using gray-on-gray moments further comprises use of lookup tables generated to map moments of the centroid of light intensity onto an edge parameter.
Claim 5
Dependent Claim
25 words
The image detection and pixel processing system of claim 1, wherein finding the first gray value is determined using context of an adjacent detector element.
Claim 6
Dependent Claim
30 words
The image detection and pixel processing system of claim 1, wherein finding the first gray value is an estimate based on interpolation of gray values of two adjacent detector elements.
Claim 7
Dependent Claim
40 words
The image detection and pixel processing system of claim 1, wherein the image processing assembly renders the subpixel area as an edge when the magnitude of the centroid of light intensity is greater than a predetermined threshold of about 1/3.
Claim 8
Dependent Claim
170 words
An image processing method using information obtained from a plurality of macrodetectors configured to receive an image, with each macrodetector composed of at least four detector elements, the method comprising the steps of determining a total light intensity value within each of said macrodetectors, determining a centroid of light intensity indicative of light intensity position within each of said macrodetectors, relating a pixel and its encompassed subpixel area to each of said corresponding macrodetector to determine the total light intensity within the pixel and the centroid of light intensity within the subpixel area, and rendering each subpixel area as an edge when magnitude of the centroid of light intensity is greater than a predetermined threshold, and evaluating the subpixel area to determine an edge, finding a first gray value on a first side of the edge, determining actual edge position, and using actual edge position and the first gray value to determine a second gray value on a second side of the edge opposite the first side of the edge.
Claim 9
Dependent Claim
170 words
An image processing method using information obtained from a plurality of macrodetectors configured to receive an image, with each macrodetector composed of at least four detector elements, the method comprising the steps of determining a total light intensity value within each of said macrodetectors, determining a centroid of light intensity indicative of light intensity position within each of said macrodetectors, relating a pixel and its encompassed subpixel area to each of said corresponding macrodetector to determine the total light intensity within the pixel and the centroid of light intensity within the subpixel area, and rendering each subpixel area as an edge when magnitude of the centroid of light intensity is greater than a predetermined threshold, and evaluating the subpixel area to determine an edge, finding a first gray value on a first side of the edge, determining actual edge position, and using actual edge position and the first gray value to determine a second gray value on a second side of the edge opposite the first side of the edge.
Claim 10
Dependent Claim
40 words
The image processing method of claim 7, wherein the step of determining actual edge position further comprises the steps of partially determining parameterization of the edge using gray-on-gray moments, and converting gray-on-gray moments to gray-on-black to uniquely define edge location.
Claim 11
Dependent Claim
41 words
The image processing method of claim 8, wherein the step of partially determining parameterization of the edge using gray-on-gray moments further comprises the step of mapping moments of the centroid of light intensity onto an edge parameter using generated lookup tables.
Claim 12
Dependent Claim
32 words
The image processing method of claim 7, wherein the step of finding the first gray value further comprises the step of evaluating gray value context of at least one adjacent detector element.
Claim 13
Dependent Claim
38 words
The image processing method of claim 7, wherein the step of finding the first gray value further comprises the step of estimating gray value context based on interpolation of gray values of two or more adjacent detector elements.
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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) | 2001-08-03 | 2002-02-02 | 2002-08-04 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 2005-08-03 | 2006-02-02 | 2006-08-04 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2009-08-03 | 2010-02-02 | 2010-08-04 | $7700.00 | Window Closed / Lapsed |