The new method of pitch detection based on morphological filtering and Hilbert-Huang transform (HHT)was proposed.Noisy speech signals were filtered by the morphological filter to remove noises and highlight pitch,and then HHT was employed to get the Hilbert-Huang spectrum and calculate instantaneous energy and its derivative.The moment of glottal opening and closing can be located accurately through muta-tion of instantaneous energy,so variation of pitch periods can be tracked accurately.Compared with other tra-ditional methods of pitch detection,the proposed method truely describes the non-stationary and non-linear characteristics of speech signals,and its analysis on voice signals is an adaptive process.The experimental re-sults show that the method gives strong noise immunity and can accurately detect pitch of speech signals in low SNR.%提出一种基于形态学滤波和 Hilbert-Huang变换 HHT (Hilbert-Huang Transform)的基音检测方法，该方法先对带噪语音信号进行形态学滤波，滤除噪声，突出基音，滤波后的信号进行 Hilbert-Huang 变换得到信号的Hilbert谱，由Hilbert谱计算瞬时能量及其导数，通过瞬时能量的突变定位声门开闭的时刻来精确地跟踪基音的变化。与传统的基音检测方法向比较，该方法真实地描述了语音信号非平稳、非线性的特性，对语音信号的分析是一种自适应的过程，实验结果表明，该方法有较强的抗噪性，在低信噪比环境下仍能够精确地提取出语音信号的基音。
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