摘 要：本文提出一种基于CELP 解码端的直线拟合的基音推导方法用于基音估计，该方法在CELP 解码端出现语音帧丢失时能够更好地恢复丢失帧中的自适应码书部分，同时，为了保证丢失帧后的正常激励信号与实际激励信号同步，文中采用对声门脉冲进行再同步来提高帧擦除掩蔽后的语音合成质量。将这两种方法在ITU-T G.729 编码标准中进行尝试，结果表明，所建议方法能够比原始方案取得更好的恢复效果，对基于CELP 模型的语音编码器帧擦除掩蔽都有很好的效果。
关键词：基音估计；帧擦除；帧擦除掩蔽；CELP
中图分类号：TN912.3 文献标识码：A 文章编号：2096-4706（2019）17-0055-04
Algorithm of Speech Frame Erasure Concealment Based on CELP
WANG Chunliu1，ZHU Huan2
（1.Nanjing Normal University Zhongbei College，Department of Information Science and Technology，Nanjing 210023，China；2.Electrical Section，Ministry of Technology，Jiangsu Tianhong Machinery Industrial Co.，Ltd.，Zhenjiang 212325，China）
Abstract：A novel pitch extrapolation based on straight line fitting in the decoder of CELP was proposed in this paper. This method can better recover the adaptive codebook part of the lost frame when the voice frame loss occurs at the CELP decoder. In addition，in order to ensure the synchronization of normal excitation signals and actual excitation signals after missing frames，a glottal pulse resynchronization method is used which improves the quality of speech synthesis after frame erasure concealment. We applied the two technologies to the ITU-T G.729 codec，the results show that the proposed method can achieve better recovery effect than the original scheme，and have good performance for frame erasure concealment of other speech codec based on CELP.
Keywords：pitch estimation；frame erasure；frame erasure concealment；CELP
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作者简介：王春柳（1989.01-），女，汉族，安徽宿州人，助教，硕士研究生，研究方向：语音编码、DSP。