This paper deals with a newly developed methodology and an approach for the pattern discrimination of plane shapes using the group-classification value as a feature parameter. Before the group-classification value is decided, the pulse row obtained by the second differentiation of the projection of the shape on the reference line is considered. As the number of the positive and the negative pulses in the pulse row varies with the postural angle of the shape, the maximum numbers of the positive and the negative pulses are decided. The group-classification value is defined from the ratio of the maximum number of the positive pulses to the sum of the maximum numbers of the positive and the negative pulses.
The author proposes a method to discriminate 22 kinds of shapes by applying the group-classification value, the minimum of the positive pulse, the maximum and minimum of the negative pulse and the pulse type. Furthermore, the proposed method is applied to the actual pattern discrimination and the result shows that 19 kinds of shapes can be discriminated when the pattern image is sampled by the 35×35 matrix pattern with every 5 degrees.