LINEAR PREDICTION ANALYSIS DEVICE, METHOD, PROGRAM, AND STORAGE MEDIUM

摘要

An autocorrelation calculation unit 21 calculates an autocorrelation RO(i) from an input signal. A prediction coefficient calculation unit 23 performs linear prediction analysis by using a modified autocorrelation R′O(i) obtained by multiplying a coefficient wO(i) by the autocorrelation RO(i). It is assumed here, for each order i of some orders i at least, that the coefficient wO(i) corresponding to the order i is in a monotonically increasing relationship with an increase in a value that is negatively correlated with a fundamental frequency of the input signal of the current frame or a past frame.

主权项

1. A linear prediction analysis method of obtaining, in each frame, which is a predetermined time interval, coefficients that can be transformed to linear prediction coefficients corresponding to an input time-series signal, the linear prediction analysis method comprising:
an autocorrelation calculation step of calculating an autocorrelation RO(i) between an input time-series signal XO(n) of a current frame and an input time-series signal XO(n−i) i samples before the input time-series signal XO(n) or an input time-series signal XO(n+i) i samples after the input time-series signal XO(n), for each i of i=0, 1, . . . , Pmax at least; and a prediction coefficient calculation step of calculating coefficients that can be transformed to first-order to Pmax-order linear prediction coefficients, by using a modified autocorrelation R′O(i) (i=0, 1, . . . , Pmax) obtained by multiplying a coefficient wO(i) (i=0, 1, . . . , Pmax) by the autocorrelation RO(i) (i=0, 1, . . . , Pmax) for each i, for each order i of some orders i at least, the coefficient wO(i) corresponding to the order i being in a monotonically increasing relationship with an increase in a period, a quantized value of the period, or a value that is negatively correlated with a fundamental frequency based on the input time-series signal of the current frame or a past frame.