METHOD AND SYSTEM FOR COMBINING MAGNETICALLY AND OPTICALLY DERIVED SIGNALS TO RECOGNIZE CHARACTERS

• US 3,876,981 A
• Filed: 08/28/1973
• Issued: 04/08/1975
• Est. Priority Date: 08/28/1973
• Status: Expired due to Term

• Current Assignee: Rolland E. Welch
• Original Assignee: Rolland E. Welch
• Inventors: Welch, Rolland E.
• Primary Examiner(s): Shaw, Gareth D.
• Assistant Examiner(s): Boudreau, Leo H.
• Application Number:
  US05/392,399
• Time in Patent Office: 588 Days
• Field of Search: 340/146.3ED,146.3D 235/61.11E,61.11D,61.7R
• US Class Current: 382/182
• CPC Class Codes: G06F 18/256 of results relating to different input data, e.g. multimodal recognition
• CPC Class Codes: G06V 10/98 Detection or correction of errors, e.g. by rescanning the pattern or by human intervention; Evaluation of the quality of the acquired patterns
• CPC Class Codes: G06V 30/2253 Recognition of characters printed with magnetic ink G06V30/2247 takes precedence

Abstract

A character recognition system and method for recognizing characters printed in magnetic ink in which recognition is enhanced by sensing the characters with both magnetic and optical transducers. At least a signal derived from the magnetic transducer output signal is combined with at least a signal derived from the optical transducer output signal either at or prior to the recognition stage.

Claims

1. A character recognition system for recognizing characters printed in magnetic ink comprising magnetic transducer means for generating at least a first transducer signal in response to the magnetic properties of each of said characters, optical transducer means for generating at least a second transducer signal in response to the optical properties of each of said characters, means for converting said at least a first transducer signal for each character to a first set of ditial feature signals for that character, means for converting said at least a second transducer signal for each character to a second set of digital feature signals for that character, and recognition means responsive to at least one feature signal from said first set of signals for each character and at least one feature signal from said second set of signals for the same character for providing an identification signal indicative of that character.

2. The system of claim 1 wherein said recognition means includes means for combining said at least one feature signal from said first set and said at least one feature signal from said second set.

3. The system of claim 1 wherein said recognition means includes AND gate means and wherein at least one feature signal from each of said sets or a signal derived from at least one feature signal from each of said sets is fed to said AND gate means.

4. The system of claim 3 wherein said recognition means further includes OR gate means and at least two of said feature signals are fed to said OR gate means.

5. The system of claim 4 wherein at least two of the total number of signals fed to said OR gate means are from different sets of said feature signals.

6. The system of claim 5 wherein the output of said OR gate means is fed to said AND gate means.

7. The system of claim 1 wherein the feature signals fed to said recognition means from at least one of said first and second sets of feature signals are insufficient by themselves to provide for positive identification of the character.

8. A character recognition system for recognizing characters printed in magnetic ink comprising magnetic transducer means for generating at least a first transducer signal in response to the magnetic properties of each of said characters, optical transducer means for generating at least a second transducer signal in response to the optical properties of each of said characters, means for converting said at least a first transducer signal for each character to first digital signals for each character, means for converting said at least a second transducer signal to second digital signals for each character, means for combining at least one of said first digital signals for each character with at least one of said second digital signals for the same character to produce at least a combined digital signal for that character, and recognition means responsive at least in part to said at least a combined signal or to signals derived from said at least a combined signal for producing an identification signal for each character.

9. The system of claim 8 wherein said characters to be recognized include vertical strokes and wherein said first digital signals indicate whether or not a vertical stroke is present.

10. The system of claim 8 wherein said second digital signals are indicative of the length of the strokes of said characters.

11. The system of claim 8 wherein said means for combining includes AND gate means.

12. The system of claim 8 further including feature signal generating means responsive to said at least a combined signal for producing said signals derived from said at least a combined signal.

13. The system of claim 12 wherein said feature signal generating means is also responsive to timing signal generating means.

14. The system of claim 8 wherein said means for combining includes matrix storage means.

15. The system of claim 14 wherein said means for combining further includes means for imputting a one-bit to said matrix storage means only when one digital signal of said first digital signals for each character and one digital signal from said second digital signals both indicate that the same part of the character is present.

16. The system of claim 15 wherein said means for imputting includes AND gate means.

17. The system of claim 14 wherein said means for combining includes means for imputting a one-bit to said matrix storage means when either one digital signal of said first digital signals for each character or one digital signal from said second digital signals for each character indicates that a part of the character is present.

18. The system of claim 17 wherein said means for imputting includes OR gate means.

19. The system of claim 14 wherein said matrix storage means includes at least a cell which is arranged to store a one-bit when a digital signal of one of said first or second digital signals for each character indicates that a part of the character is present and to store an additional one-bit when a digital signal of the other of said first or second digital signals for each character indicates that the same part of the character is present.

20. A character recognition system for recognizing characters printed in magnetic ink comprising magnetic transducer means for generating a first transducer signal in response to the magnetic properties of each of said characters, optical transducer means for generating a second transducer signal in response to the optical properties of each of said characters, first converting means for converting each of said first transducer signals to a first set of digital feature signals, second converting means for converting each of said second transducer signals to a second set of digital signals, preliminary recognition means responsive to said second set of digital signals for providing a preliminary character identification signal and final recognition means responsive to said preliminary identification signal and to at least a feature signal from said first set of digital signals for providing a final character identification signal.

21. A method of character recognition for recognizing characters printed in magnetic ink comprising the steps of, generating at least a first transducer signal in response to the magnetic properties of each of said characters, generating at least a second transducer signal in response to the optical properties of each of said characters, converting each of said at least a first transducer signal to a first set of digital feature signals for each character, converting each of said at least a second transducer signal to a second set of digital feature signals for each character, and deriving an identification signal for each character in response to at least one digital signal from said first set of signals for each character and at least one digital signal from said second set of signals for the same character.