Showing papers on "Optical character recognition published in 1969"

Optical character recognition system using parallel different scan signal processors to feed higher speed asynchronous recognition register

Abstract: An Optical Character Recognition (OCR) system which scans a character to be recognized to produce a scanner output signal which feeds parallel different processors, the outputs of which are inspected sequentially in real time at a rate higher than the scan signal frequency by a recognition mask system The parallel different processors derive from the scanner output signal a plurality of different though related output signals which in effect represent a plurality of scans of the character in different modes, thereby reducing the need to rescan nonstandard characters in such different modes The parallel different processors utilize (1) bilevel quantizers with different threshold levels, thereby to provide a normalized binary signal for characters of nonstandard contrast, and (2) stacking shift registers, operating at different speeds, for receiving the outputs of the bilevel quantizers, thereby to provide a normalized binary signal for characters of nonstandard height The information in the stacking registers, which store at any instant a part only of the scanner output signal, is periodically supplied, by parallel transmission, to respective groups of nonadjacent initial stages of a high-speed recognition register which operates asynchronously with the scanner and at a much higher speed than the scanner A set of recognition masks, each designed to provide a maximum output in response to a signal representative of a particular character, is coupled to nonadjacent subsequent stages of the recognition register such that complete binary signals from the stacking register, representing differently processed versions of the scanner output signal, are inspected sequentially In the course of this operation each mask inspects every binary signal Identity of the scanned character is indicated by the mask which produces the highest output

Optical character recognition system including scanned diode matrix

Abstract: An optical character recognition system comprising a photohead which scans successively a character image to be recognized information being transferred during the scan into a number of tapped delay lines such that information resulting from one complete scan can be presented simultaneously to a detector arrangement capable of recognizing predetermined features of a plurality of different characters, signals indicative of such recognition being fed into a multistage shift register the contents of which are sampled by character detector means which provides a final output signal when predetermined signal state is obtained in selected stages of the shift register.

Optimizing a video preprocessor for OCR

Abstract: This paper describes how optimal video preprocessor performance can be achieved using a software recognition system and a set of controlled experiments. It basically involves optimizing on a constant threshold and then using recognition logic designed from that threshold to optimize an adaptive threshold function or threshold operator. By using this technique, the video preprocessor can be optimized early In the development of an OCR (Optical Character Recognition) machine. The software recognition system is described and experimental data is presented to illustrate the procedures.