US5018216A
Expired / Lapsed
US
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Method of extracting a feature of a character
Assignee: Ricoh Co Ltd
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Filing: 1989-07-11
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Granted: 1991-05-21
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Expires: 2009-07-11
Abstract
Abstract A method of extracting a feature of a character includes the steps of dividing a contour image of a character into a plurality of segments by a pair of dividing lines provided for the contour image, dividing each of the segments into a plurality of sub-segments, combining the sub-segments together to thereby form a plurality of combined segments in accordance with a predetermined rule indicative of a combination of the sub-segments, and extracting a feature of each of the combined segments.
Inventors
- 👤 Keiji Kojima
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-28 08:15
CPC Classifications
G; G06; G06V; G06V30/00; G06V30/10; G06V30/18; G06V30/182
Claims Analysis
Total Claims: 19
Claim 1
Independent Claim
214 words
A method of extracting a feature of a character comprising the steps of: (a) dividing a contour image of a character into a plurality of segments by referring to a pair of dividing lines provided for said contour image, said dividing lines crossing said contour image so that said dividing lines cross a width of a line forming said character, and said contour image being divided into the plurality of segments at dividing points selected from cross points where said dividing lines cross said contour image, said step of dividing said contour image including the steps of: (1) tracing white or black pixels arranged along said contour image; (2) assigning said white or black pixels direction codes indicative of respective directions of movement of said tracing; and (3) defining said pair of dividing lines by calculating a distribution of each of said direction codes; (b) dividing each of said segments into a plurality of sub-segments; (c) combining said sub-segments together to thereby form a plurality of combined segments in accordance with a predetermined rule indicative of a combination of said sub-segments, said predetermined rule representing that sub-segments located on each of said dividing points being included in an identical one of said combined segments; and extracting a feature of each of said combined segments.
Claim 2
Independent Claim
214 words
A method of extracting a feature of a character comprising the steps of: (a) dividing a contour image of a character into a plurality of segments by referring to a pair of dividing lines provided for said contour image, said dividing lines crossing said contour image so that said dividing lines cross a width of a line forming said character, and said contour image being divided into the plurality of segments at dividing points selected from cross points where said dividing lines cross said contour image, said step of dividing said contour image including the steps of: (1) tracing white or black pixels arranged along said contour image; (2) assigning said white or black pixels direction codes indicative of respective directions of movement of said tracing; and (3) defining said pair of dividing lines by calculating a distribution of each of said direction codes; (b) dividing each of said segments into a plurality of sub-segments; (c) combining said sub-segments together to thereby form a plurality of combined segments in accordance with a predetermined rule indicative of a combination of said sub-segments, said predetermined rule representing that sub-segments located on each of said dividing points being included in an identical one of said combined segments; and extracting a feature of each of said combined segments.
Claim 3
Dependent Claim
27 words
A method of extracting a feature of a character as claimed in claim 1, wherein said sub-segments are combined together for a every predetermined number of sub-segments.
Claim 4
Dependent Claim
65 words
A method of extracting a feature of a character as claimed in claim 1, wherein said predetermined rule is in the form of a table which defines a first number for indicating said respective segments, a second number for indicating said respective sub-segments formed for every segment, and a third number for indicating said respective combined segments formed by combining some of said sub-segments together.
Claim 5
Dependent Claim
36 words
A method of extracting a feature of a character as claimed in claim 1, wherein said pair of dividing lines are parallel to each other and provided at upper and lower portions of said contour image.
Claim 6
Dependent Claim
34 words
A method of extracting a feature of a character as claimed in claim 1, wherein the feature of each of said combined segments is extracted from direction codes assigned pixels forming said contour image.
Claim 7
Dependent Claim
30 words
A method of extracting a feature of a character as claimed in claim 5, wherein said feature of each of said combined segments includes a histogram of said direction codes.
Claim 8
Dependent Claim
45 words
A method of extracting a feature of a character as claimed in claim 1, wherein a number of sub-segments to be formed by dividing each of said segments is selected based on a relationship between each of said segments and said pair of dividing lines.
Claim 9
Independent Claim
193 words
A method of extracting a feature of a character, comprising the steps of: dividing a contour image of a character into a plurality of segments by referring to a pair of dividing lines provided for said contour image, said dividing lines crossing said contour image so that said dividing lines cross a width of a line forming said character, and said contour image being divided into the plurality of segments at dividing points selected from cross points where said dividing lines cross said contour image; dividing each of said segments into a plurality of sub-segments; combining said sub-segments together to thereby form a plurality of combined segments in accordance with a predetermined first rule indicative of a combination of said sub-segments, said predetermined rule representing that sub-segments located on each of said dividing points being included in an identical one of said combined segments; combining said combined segments together to thereby form a plurality of recombined segments in accordance with a predetermined second rule indicative of a recombination of said combined segments; extracting a first feature of each of said combined segments; and extracting a second feature of each of said recombined segments.
Claim 10
Independent Claim
193 words
A method of extracting a feature of a character, comprising the steps of: dividing a contour image of a character into a plurality of segments by referring to a pair of dividing lines provided for said contour image, said dividing lines crossing said contour image so that said dividing lines cross a width of a line forming said character, and said contour image being divided into the plurality of segments at dividing points selected from cross points where said dividing lines cross said contour image; dividing each of said segments into a plurality of sub-segments; combining said sub-segments together to thereby form a plurality of combined segments in accordance with a predetermined first rule indicative of a combination of said sub-segments, said predetermined rule representing that sub-segments located on each of said dividing points being included in an identical one of said combined segments; combining said combined segments together to thereby form a plurality of recombined segments in accordance with a predetermined second rule indicative of a recombination of said combined segments; extracting a first feature of each of said combined segments; and extracting a second feature of each of said recombined segments.
Claim 11
Dependent Claim
79 words
A method of extracting a feature of a character as claimed in claim 8, wherein said first extracted feature is used for character recognition, and said second extracted feature is used for identifying a classification to which said character is related, and wherein when said character is subjected to a character recognition procedure, said character is classified based on said second extracted feature, and then said first extracted feature is compared with a reference feature related to said classification.
Claim 12
Dependent Claim
29 words
A method of extracting a feature of a character as claimed in claim 9, wherein said combined segments are combined together for a every predetermined number of combined segments.
Claim 13
Dependent Claim
51 words
A method of extracting a feature of a character as claimed in claim 8, wherein said combined segments are combined together so that combined segments among said combined segments located between said pair of dividing lines are used in common in order to form some of said plurality of recombined elements.
Claim 14
Dependent Claim
53 words
A method of extracting a feature of a character as claimed in claim 8, wherein said combined segments are combined together so that combined segments among said plurality of combined segments located at corner portions of said character are used in common in order to form some of said plurality of recombined segments.
Claim 15
Dependent Claim
33 words
A method of extracting a feature of a character as claimed in claim 8, wherein said second rule is defined in the form of a formula showing how to combine said combined segments.
Claim 16
Dependent Claim
71 words
A method of extracting a feature of a character as claimed in claim 8, wherein said step of: dividing said contour image comprises the steps of tracing white or black pixels arranged along said contour image, assigning said white or black pixels direction codes indicative of respective directions of the movement of said tracing, and defining said pair of dividing lines by calculating a distribution of each of said direction codes.
Claim 17
Dependent Claim
36 words
A method of extracting a feature of a character as claimed in claim 8, wherein said pair of dividing lines are parallel to each other and provided at upper and lower portions of said contour image.
Claim 18
Dependent Claim
34 words
A method of extracting a feature of a character as claimed in claim 8, wherein the feature of each of said combined segments is extracted from direction codes assigned pixels forming said contour image.
Claim 19
Dependent Claim
30 words
A method of extracting a feature of a character as claimed in claim 16, wherein said feature of each of said combined segments includes a histogram of said direction codes.
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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) | 1994-05-20 | 1994-11-19 | 1995-05-21 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1998-05-20 | 1998-11-19 | 1999-05-21 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2002-05-20 | 2002-11-19 | 2003-05-21 | $7700.00 | Window Closed / Lapsed |