JPS5779588A - Optical character reader - Google Patents

Abstract

PURPOSE:To perform accurate reading operation by determining more than one expected characters for a character pattern quantized by photoelectric conversion, finding their similarity values, and thus recognizing the feature difference of the character pattern precisely. CONSTITUTION:A character entered in a document is converted by a photoelectric converting circuit 1 into an analog signal, which is converted into quantized data through a quantizing circuit 2. Then, a preprocessing circuit 3 performs noise removal, etc., and a normalizing circuit 6 normalizes the whole character pattern. Further, a similarity calculating circuit 7 refers to standard character patterns in a dictionary memory 8 to decide two expected characters having higher similarity values for the normalized character pattern, and calculates their similarity values to send them to a discriminating circuit 4. When the difference in similarity value between those two expected characters is greater than a prescribed value and the expected character having the higher similarity value has the higher similarity value than a prescribed value, the character is employed to output its character code to a data line l1. Consequently, the feature difference of the character pattern is recognized precisely for accurate reading operation.