一种低信噪比语音的增强算法

为改善低信噪比环境下语音的质量，论文提出了一种新的语音增强算法。算法首先根据噪声频谱的高斯统计模型得到用先验信噪比形式表示的噪声频谱估计值，然后利用帧内、帧间平滑算法估计每一个频点的先验信噪比，从而能够更好地跟踪先验信噪比的变化。算法接着引入一种简便的估计语音在每一个频点出现概率的方法，得出一种新的语音增强算法。客观测试和非正式听音测试表明：该算法在几乎不损伤语音清晰度的前提下，能够更好地抑制低信噪比语音增强所产生的音乐噪声，同时使语音信噪比得到了明显提高。

Enhancement Algorithm for Low Signal to Noise Ratio Speech

This paper proposes a new speech enhancement algorithm to improve the quality of speech in low SNR environment.The algorithm estimates the noise spectrum in the form of prior SNR according to its Gaussian statistical model firstly.Then it estimates the prior SNR of each frequency bin utilizing the intra-frame as well as inter-frame smoothness to trace the quick change of the prior SNR.It also introduces a simple method to compute the speech presence probability to each frequency bin and obtain the new speech enhancement algorithm. Objective measurement combined with informal listening test shows that the new algorithm is more effective in eliminating musical noise and improving SNR obviously without significantly impairing the intelligibility of speech.