采用扩展型双线性变换法将耳语音转换为正常语音的研究

提出了一种采用扩展型双线性变换将耳语音转换为正常语音的方法。根据耳语音在不同频段的共振峰偏移程度不同,将耳语音的频谱进行分段处理,在此基础上建立耳语音转换为正常语音的转换函数。由于耳语音在各频段相对于正常语音非线性偏移,在双线性变换函数中引入扩展因子,使其对频谱的非线性偏移与对共振峰带宽的压缩更加符合耳语音转换为正常语音的实际转换需求,有效减小了转换语音与正常语音的谱失真距离。实验结果表明,本文的转换语音在音质和可懂度上均得到了有效提高。 

Research of conversion from whispered speech to normal speech by the extended bilinear transformation

One method of conversion from whispered speech to formal speech based on the extended bilinear transformation is proposed.On account of the different deviation degrees of the whisper's formants in different frequency bands,the spectrum of the whispered speech will be processed in the separate partitions of this paper.On the basis of this spectrum,we will establish a conversion function able to usefully convert whispered speech to formal speech. Because of the whisper's non-linear offset in relation to normal speech,this paper introduces an expansion factor in the bilinear transform function making it correspond more closely to the actual conversion demands of whispered speech to formal speech.The introduction of this factor takes the non-linear move of the spectrum and the compression of the formant bandwidth into consideration,thus effectively reducing the spectrum distortion distance in the conversion.The experiment results show that the conversion presented in this paper effectively improves both the sound quality and the intelligibility of whispered speech.