Computer Recognition of Figures through Decomposition

A method for computer recognition of plane figures is described. For each figure, its integral projection along a certain direction is defined. This is obtained by intersecting the figure with a set of lines parallel to the chosen direction and considering the lengths of the connected segments of the intersections as a function of the location of the lines. Discontinuities in the integral projections reveal in general the existence of strokes along the corresponding directions and this way a figure can be decomposed into certain basic strokes. The information whether certain strokes appear or not in a given figure and their relative position can be used for the classification of the figure. This method was implemented and tested on multifont lower-case typewritten letters. Recognition rates around 98% were achieved on the testing sets.