基于离散余弦变换的波形内插语音编码算法  

Waveform Interpolation Speech Coding Based on DCT

作　　者：刘靖宇[1] 鲍长春[1] 李如玮[1] 

机构地区：[1]北京工业大学电子信息与控制工程学院语音与音频信号处理研究室,北京100124

出　　处：《电子学报》2009年第7期1599-1605,共7页Acta Electronica Sinica

基　　金：北京市教委科技发展项目(No.KM200710005001);国家自然科学基金(No.60372063);北京市自然科学基金(No.4042009)

摘　　要：针对波形内插(Waveform Interpolation,WI)语音编码的特征波形分解问题,本文首先提出了基于离散余弦变换(Discrete Cosine Transform,DCT)的特征波形分解方法,避免了复杂的特征波形对齐运算;其次,针对WI的相位重建问题,提出了清/浊音相位判决和浊音相位分类的方法,提高了重建语音质量;最后,分别构建了速率为2.0kbps和1.6kbps的DCT-WI声码器.主观MOS分表明,2.0kbps的DCT-WI声码器质量优于2.4kbps MELP声码器,1.6kbps的DCT-WI声码器亦取得了良好的听觉效果.Characteristic waveform （CW） decomposition based on discrete cosine transform （DCT） is proposed firstlyin waveform interpolation （WI） speech coding. The complicated CW alignment operation is cancelled by using this method. Secondly, a new unvoiced/voiced phase decision method and the classification method of voiced phase are proposed with respect to phase reconstruction.Finally,DCT-WI coders at 2.0kbps and 1.6kbps are designed, respectively. The subjective MOS test results indicate that the 2.0kbps DCT-WI coder outperforms 2.4kbps MELP coder and the 1.6kbps DCT-WI coder also has a good performance.

关 键 词：语音编码 波形内插 特征波形 离散余弦变换 特征波形对齐 相位重建 

分 类 号：TN912.3[电子电信—通信与信息系统]