Character identifying apparatus

• US 4,701,961 A
• Filed: 04/26/1985
• Issued: 10/20/1987
• Est. Priority Date: 04/27/1984
• Status: Expired due to Fees

• Current Assignee: Fuji Electric Company Limited (Fuji Electric Systems Company Limited)
• Original Assignee: Fuji Electric Company Limited (Fuji Electric Systems Company Limited)
• Inventors: Hongo, Yasuo
• Primary Examiner(s): Boudreau, Leo H.
• Application Number:
  US06/727,889
• Time in Patent Office: 907 Days
• Field of Search: 382/30, 382/33, 382/34, 382/47, 382/27
• US Class Current: 382/218
• CPC Class Codes: G06V 10/751 Comparing pixel values or logical combinations thereof, or feature values having positional relevance, e.g. template matching

Abstract

A character identifying device generates a core bit matrix and a mask bit matrix for each reference character pattern scanned by a television camera or like device. The two matrices represent binary coded representation of a reference character pattern at two different threshold levels. An enlarged matrix representation and a contracted matrix representation of the same unknown character pattern are compared to the core bit matrix and the mask bit matrix, respectively, of each reference character pattern and corresponding correlation output signals are generated to unable the identification of the reference character pattern most closely correlated to the unknown character pattern.

Claims

1. A character identifying device for identifying an unknown character pattern by processing input video signals generated by scanning the unknown character pattern and reference video signals generated by scanning reference character patterns, the device comprising:

binary coding means for generating reference and input binary coded signals corresponding respectively to the reference and input video signals;

feature data extracting means for dividing said reference binary coded signals into segments and for extracting feature data from said segments, wherein said segments of each of said reference binary coded signals correspond to different portions of the corresponding reference character patterns, and wherein the feature data extracted from each of said segments includes coupling features identifying the corresponding one of said reference character patterns;

coupling characteristic analyzing means for analyzing said coupling features of said segments by processing said feature data;

bit matrix forming means for generating at least one bit matrix for each of the reference character patterns by combining selected ones of said segments in accordance with the coupling features thereof, each of said bit matrices comprising a plurality of matrix elements having a first value if said matrix element corresponds to a portion of that reference character pattern or a second value if said matrix element does not correspond to a portion of that reference character pattern;

accumulation matrix forming means for generating for each of said reference character patterns an accumulation matrix having substantially the same size as the at least one bit matrix for the corresponding reference character pattern, each of said accumulation matrices including a plurality of accumulation matrix elements each corresponding to a different one of the elements in the at least one bit matrix for the corresponding reference character pattern and each of said accumulation matrix elements having values substantially equal to the number of corresponding elements of the at least one bit matrix for the same reference character patterns which have said first value;

means for forming, for each of said accumulation matrices, a core bit matrix and an associated mask bit matrix each said core bit and mask bit matrix including a plurality of core bit elements and mask bit elements, respectively, each associated with a corresponding accumulation matrix element wherein each of said core bit elements has said first value and each of said associated mask bit elements has said second value if the value of the corresponding accumulation matrix element is greater than a first accumulation value and a second accumulation value, respectively, and bears a predetermined relationship to other core bit elements and mask bit elements, respectively;

operating means for generating an enlarged bit matrix and a contracted bit matrix from said input binary coded signals, said enlarged bit matrix including a plurality of bit matrix elements representing an enlargement of said unknown character pattern and said contracted bit matrix including a plurality of bit matrix elements representing a contraction of said unknown character pattern; and

first calculating means for comparing the elements of said enlarged bit matrix and said core bit matrices for said reference patterns to obtain character separation distances; and

second calculating means for comparing the elements of said contracted bit matrix and said mask bit matrices for said reference patterns to obtain character smudge distances;

whereby said character separation distances and said character smudge distances can be used to identify said known character pattern as one of said reference character patterns.

2. A character identifying device according to claim 1, further including first, second, and third memories for storing said accumulation matrices, said core bit matrices, and said mask bit matrices, respectively.