基于听觉感知特性的语音质量客观评价方法

讨论了基于MFCC (Mel-frequency cepstral coefficients)特征参数的语音质量客观评价方法Mel-CD (Mel-cepstral distance measure).根据心理声学原理将Johannesma提出的人耳听觉模型和非线性压缩变换引入MFCC特征参数的提取过程,用Gammatone滤波器组对人耳基底膜进行仿真.利用改进后的MFCC作为语音信号特征参数,提出了一种更加符合人耳听觉感知特性的客观评价方法——Mel-GD (Mel-cepstral gammatone filter bank distance measure).性能测试结果表明:所提算法与Mel-CD算法在时间复杂度上保持一致,评价结果的主观与客观的相关度提高了4.9%,平均估计偏差改善了45.5%. 

Objective Evaluation Method of Speech Quality Based on Auditory Perceptual Properties

Based on Mel-frequency cepstral coefficients (MFCC), Mel-cepstral distance measure (Mel-CD) algorithm used for the objective evaluation of speech quality was analyzed. According to the theory of psychoacoustics, a human auditory model proposed by Johannesma and nonlinear compression were applied to extracting MFCC. Gammatone filter bank was used to simulate the basilar membrane. Mel-cepstral gammatone filter bank distance measure (Mel-GD) based on the improved MFCC was proposed, which was more in accordance with the auditory perceptual properties. Performance testing results showed that the proposed algorithm compared favorably with the Mel-CD in time complexity, the correlation degree between objective evaluation and subjective evaluation was improved by 4.9%, and estimation bias was decreased by 45.5%.