Computer-Automated Design of Multifont Print Recognition Logic
by L. A. Kamentsky, C.-N. Liu
A computer program has been written to design character recognition logic based on the processing of data samples. This program consists of two subroutines: (1) to search for logic circuits having certain constraints on hardware design, and (2) to evaluate these logics in terms of their discriminating ability over samples of the character set they are expected to recognize. An executive routine is used to apply these subroutines to select a complete logic with a given performance and complexity. This logic consists of 39 to 96 AND gates connected to a shift register and a table look-up or resistance network comparison system.
The methods were applied to the design of recognition logics for the 52 upper and lower case characters of IBM Electric Modern Pica type font and lower case Cyrillic characters scanned from Russian text. In both cases when the logics were tested on data different from that used to design the logics, the substitution rate was about one error per thousand. A single logic was designed to read two different Cyrillic fonts. For this design, an error rate of one error per hundred characters was observed.
Several experiments are reported on a number of logics designed for typewritten data, and single- and two-font Cyrillic data. The performances of different recognition systems are compared as a function of the complexity of the recognition logics.