Feature extracting and sorting method of character pattern

TLDR: In this paper, the variation pattern of number of runs in terms of horizontal and vertical directions of a character pattern is extracted as the feature of the character pattern. But the feature vectors obtained at the registers 22X and 22Y are fed to a comparator 24 to be compared with the contents of a feature dictionary memory 27 for sorting.

Abstract: PURPOSE:To extract stable feature with simple processing, by obtaining a variation pattern of numbers of runs in terms of horizontal and vertical directions of a character pattern and then extracting the variation pattern of number of runs of two types as the feature of the character pattern. CONSTITUTION:A reading circuit 12 give horizontal and vertical raster scans to the character pattern in a character pattern memory 10 and feeds the character pattern data to white/black variation detectors 14X and 14Y. The number of black runs on each scanning line in X and Y directions are counted by black run counters 16X and 16Y. The difference is obtained by differential detectors 20X and 20Y between the number of runs obtained by counters 16X and 16Y and the number of runs on the immediately preceding line which are held temporarily in registers 18X and 18Y. The number of runs on the present scanning line are set to registers 22X and 22Y, and the feature vectors obtained at the registers 22X and 22Y are fed to a comparator 24 to be compared with the contents of a feature dictionary memory 27 for sorting.