FILTER COEFFICIENT GENERATING METHOD

摘要

PURPOSE:To obtain a coefficient to be set in an FIR filter mechanically and easily and to obtain the coefficient for utilizing the FIR filter at a maximum by finding many extremal values of an impulse response curve and extracting a specific number of extremal values in the decreasing order of the absolute values of data values. CONSTITUTION:A signal processor 23 consists of an initial reflected sound generation part 231 which simulates an initial reflected sound and a rear reverberation sound generation part 232 which simulates a reflected sound (reverberation sound) following the initial reflected sound. Here, the object characteristic impulse response curve is found by an initial reflected sound generating means 232-1-1. This impulse response curve is found by measuring an actual sound field. Many extremal values of the impulse response curve are found and a desired number of data and their generation time data (delay quantity) are extracted in the decreasing order of the absolute values among the found extremal values, thereby finding the filter coefficient mechanically.