US4251799A
Expired / Lapsed
US
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Optical character recognition using baseline information
Assignee: International Business Machines Corp
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Filing: 1979-03-30
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Granted: 1981-02-17
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Expires: 1999-03-30
Abstract
Abstract An Optical Character Recognition (OCR) system for printed characters uses information about baseline location to assist in registration, segmentation, recognition and the separation of underscoring. Selected ones of the sensor elements in the OCR scanning array are identified as defining a baseline searching window and the outputs of these selected elements are utilized to detect baseline information for each character or group of characters in a printed line.
Inventors
- 👤 Chentung R. Jih
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-31 05:04
CPC Classifications
G; G06; G06V; G06V30/00; G06V30/10; G06V30/14; G06V30/146; G06V30/1475; G06V30/1478
Claims Analysis
Total Claims: 4
Claim 1
Independent Claim
78 words
A method for processing image data from a scanning array which scans characters in a scanning direction to locate a baseline, comprising the steps of calculating a horizontal projection histogram of said characters at a plurality of periodic spaced locations along said scanning direction, detecting a peak characteristic of each of said histograms, and averaging said detected peak characterstics of said histograms to produce an estimate of the skew of said baseline with respect to said scanning direction.
Claim 2
Independent Claim
78 words
A method for processing image data from a scanning array which scans characters in a scanning direction to locate a baseline, comprising the steps of calculating a horizontal projection histogram of said characters at a plurality of periodic spaced locations along said scanning direction, detecting a peak characteristic of each of said histograms, and averaging said detected peak characterstics of said histograms to produce an estimate of the skew of said baseline with respect to said scanning direction.
Claim 3
Dependent Claim
37 words
The method in accordance with claim 1 including the step of utilizing said estimated baseline data to dynamically alter said scanning array so that said scanning array follows said estimated baseline to process the character image data.
Claim 4
Dependent Claim
17 words
The method in accordance with claim 1, in which a histogram is calculated for each scanned character.
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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) | 1984-02-17 | 1984-08-18 | 1985-02-17 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1988-02-17 | 1988-08-18 | 1989-02-17 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1992-02-17 | 1992-08-18 | 1993-02-17 | $7700.00 | Window Closed / Lapsed |