Dynamic time warping (DTW) apparatus for use in speech recognition systems

摘要

There is disclosed a dynamic time warping (DTW) apparatus for use in a speech recognition system which also performs wordspotting or speaker verification based on speech recognition techniques. The DTW apparatus has the capability of processing given different groups of coefficients and doing such processing to arrive at Euclidean and dynamic distances independent of the number of coefficients in the group. Essentially the DTW can process 8, 16 or 24 coefficients and provide distance measurements based on such coefficients which will enable the same stored template to be utilized in comparing speech utterances as defined by the coefficients with stored template data. The configuration of the DTW is such that rapid processing can occur whereby the unit can process a large number of frames in a relatively short period, as the number of frames processed is a function of the number of coefficients in the processed group and can process different numbered coefficients in a rapid and reliable manner. The DTW also minimizes the template memory requirements. Only one copy of each template is stored in template memory.