基于Hilbert-Huang变换的语音合成基音标注搜索新算法

A new pitch annotation search algorithm based on Hilbert-Huang transformation for speech synthesis

在TD-PSOLA语音合成系统中,基音标注的准确性是一个非常重要的因素。针对传统的短时自相关函数和小波算法准确性不高和没有自适应性的缺点,提出一种基于Hilbert-Huang变换的基音标注方法。该算法通过Hilbert-Huang变换分析语音,具有自适应性,根据自身情况选择基函数,分解过程满足条件自动停止。采用文中自适应算法对整段非平稳语音信号进行基音标注,其中浊音段、过渡段采用Hilbert-Huang变换进行标注,清音段、非语音段用相近基音周期插值。实验证明,相比自相关方法、小波方法,文中算法反映了一帧内准周期的细微变化,适应性较好。对于频率不同的男声和女声,准确度可达到90%以上。

The pitch annotation accuracy is a very important factor in the TD-PSOLA speech synthesis system. In allusion to the shortcomings of low accuracy and lack of adaptability of the traditional short-term auto-correlation function and wavelet algorithm,a pitch annotation method based on Hilbert-Huang transformation is proposed. The algorithm analyzes the speech by means of Hilbert-Huang transformation,has adaptability,and selects basis functions according to its own conditions. The decomposition process of the algorithm stops automatically when the conditions are satisfied. The adaptive algorithm is adopted in this paper to conduct pitch annotation for the whole segment of non-stationary speech signals,in which the voiced speech segment and transition segment are marked by means of Hilbert-Huang transformation,and the voiceless speech segment and non-voice segment are interpolated with the similar pitch period. The experiment shows that in comparison with the auto-correlation method and wavelet method,the algorithm in this paper reflects the subtle variation of the quasi-period in a frame,has good adaptability,and has over 90% of accuracy degree for male and female voices with different frequencies.