Pattern recognizing device with pattern matching in slant parallelogrammic blocks of widths dependent on classified reference pattern lengths

摘要

On pattern matching an input pattern arranged along a first time axis to each concatenation of patterns selected from reference patterns and arranged along a second time axis with feature vectors of the input pattern and the concatenation placed at a common frame period, a dynamic programming algorithm is used by classifying the reference patterns into classes in compliance with reference pattern lengths and by giving variable block widths to slant parallelogrammic blocks of a common block slope. The variable widths should be decided for the respective classes. Preferably, a k-th class comprises a reference pattern of a reference pattern length which is not shorter than pkW and is shorter than β(k + 1)W, where β represents the block slope and W, a fundamental block width determined by the block slope under a minimum of the reference pattern lengths. In this event, the variable block width is equal to kW. The algorithm is carried out by scaling the first time axis, not by the frame period, but by block numbers assigned to slant parallelogrammic blocks having the fundamental width in common and by checking whether or not each block number is an integral multiple of k.