Method and device for determining the tonality of an audio signal

摘要

PCT No. PCT/EP96/00550 Sec. 371 Date Aug. 13, 1997 Sec. 102(e) Date Aug. 13, 1997 PCT Filed Feb. 9, 1996 PCT Pub. No. WO96/25649 PCT Pub. Date Aug. 22, 1996The tonality of an audio signal is determined by a method which includes the steps of blockwise frequency transforming a digital input signal x(n) to create a real positive-value representation X(k) of the input signal, where k designates the index of a frequency line, and determining the tonality T of the signal component for the frequency line k according to the following equation: where F1 is the filter function of a first digital filter with a first, differentiating characteristic, F2 is the filter function of a second digital filter with a second, flat or integrating characteristic or with a characteristic which is less strongly differentiating than the first characteristic, and d1 and d2 are integer constants which, depending on the filter parameters, are so chosen that the delays of the filters are compensated for in each case.