Abstract: Traditional AMDF and its improved algorithm LV-AMDF based pitch detection method easily causes the double or half error.For this problem，this paper analyzes the characters of functions of AMDF and LV-AMDF and their shortages on pitch detection，and then proposes amplitude compensation based AMDF to detect the pitch.This algorithm decreases the occurring of double-frequency and half-frequency errors and increases the detection precision.The experiments show that the proposed algorithm performs better on pitch detection compared with AMDF and LV-AMDF methods.

Key words: pitch detection algorithm, Average Magnitude Difference Function（AMDF）, Length-Varied AMDF, amplitude compensation

摘要： 传统的基于AMDF及其改进算法LV-AMDF容易导致检测基音周期时产生加倍、减半等错误。针对该现象，分析了AMDF、LV-AMDF函数的特性及其用于基音检测时存在的不足，提出了幅值补偿AMDF算法来检测基音周期，降低了基音检测中经常出现的半频、倍频错误，提高了检测的精度。实验表明该方法基音检测性能优于AMDF和LV-AMDF的方法。

关键词: 基音检测, 平均幅度差函数（AMDF）, 变长AMDF, 幅值补偿