Importance

Loading Importance Indicators...

Abstract

A method and system for recognizing a time varying waveform signal subject to amplitude distortions such as experienced with optical or magnetic printed character reading systems for scanning documents such as bank checks and the like. The variable amplitude waveform is sampled at predetermined time intervals representing predetermined spacings across a dimension of the character being read and difference values related to the sample amplitude ratio values between adjacent samples are calculated to develop a difference waveform or signature. This difference waveform may then be compared to a set of templates representing characters expected to be recognized. The amplitude ratio value of each sample may also be compared to that of a previous sample to determine the direction of the slope of the waveform at selected points wherein rising, falling or no change slope direction identifiers may be compared to a set of templates of characters expected to be read. The method eliminates incorrect character reads resulting from signal amplitude distortions due to system electrical circuit characteristics, various printing methods and other anomalies which tend to distort signals generated by optical or magnetic reading devices.

Loading the Abstract Image...

First Claim