A Pitch Detection Algorithm Based on AMDF and ACF

Abstract

The paper proposes a pitch detection algorithm based on the short-time average magnitude difference function (AMDF) and the short-term autocorrelation function (ACF). At first, AMDF values are computed by AMDF algorithm for a frame of speech signal. And then ACF values are computed by ACF algorithm for the AMDF values. In order to decreases computational expense and complexity, the AMDF values of the frame of speech signal are then transformed into one bit signals. The method can also decrease the effects of amplitude and formants the speech signal for pitch detection. The pitch period is calculated by ACF algorithm for the one bit signals. The multiplication operation for short-time autocorrelation function of the one bit signals is replaced by simple addition operation. The algorithm can largely reduce its computational cost compared with calculating ACF directly. The experiments show that the algorithm can decreases computational expense and complexity compared with ACF algorithm. The algorithm can decrease the error rate of pitch detection compared with AMDF algorithm. The proposed algorithm is easy to implement in real-time signal processing.