JPS5779587A - Optical character reader - Google Patents

Abstract

PURPOSE:To perform efficient reading operation by quantizing document data for one line of a document and classifying the quantized data by classes extracting the features, and converting resolution corresponding to the classes. CONSTITUTION:An analog signal for one line of a document, outputted through the scanning of a photoelectric converting circuit 1, is converted into binary-coded, quantized data through a quantizing circuit 2. Then, the one-line quantized data stored in a line buffer 3 is supplied to a feature extracting circuit 4, which detects complexity by the thickness of lines of a character pattern to output class-discrimination information which corresponds to the complexity. Further, a resolution converting circuit converts the resolution of the data in the line buffer 3 corresponding to the discrimination information and stored the result in a line buffer 7. A control information storage part 6, on the other hand, limits a storage area required to read the contents of an external storage device 8 corresponding to the discrimination information, and a standard character pattern in the area is converted similarly by a 2nd resolution converting circuit 9 and loaded into a dictionary memory 10. Then, the data in the buffer 7 is compared with the contents of the memory 10 through a reading circuit 11 to discriminate the character.