基于相位声码器法的音乐信号正弦分量检测

Sinusoidal Components Detection of Misical Signal Based on Phase Vocoder Method

设计和实现一种基于相位声码器的音乐信号正弦分量检测方法,该方法将STFT等效为一组均匀滤波器,将各正弦分量分离,并由各通道输出的相位变化率估计正弦分量的瞬时频率,然后通过寻找STFT通道中心频率与瞬时频率映射的定点进行正弦分量检测;同时,针对原始相位声码器的缺点,设计了一个多采样率、非均匀滤波器组对其进行改进。实验结果表明,该方法具有良好的瞬时频率跟踪性能,可作为音乐信号多音高估计的分析前端。

A sinusoidal components detection method of misical signal based on phase vocoder is designed. It regards the STFT as a uniform filter bank by which the sinusoidal components are separated from each other,and their instantaneous frequency is estimated with the phase change rate of the STFT channals＇ output. To overcome the shortage of original phase vo coder,an advanced method is also proposed which is based on a multi- sampling rates and nonuniform filter bank. The experiment results show that this method has good performance in tracking instantaneous frequencies, so it can be used as the front - end of the melody line extraction system.