Department of Psychology, Barnard College, Columbia University, New York, New York 10027, USA.
J Acoust Soc Am. 2011 Oct;130(4):2173-8. doi: 10.1121/1.3631667.
Linear prediction is a widely available technique for analyzing acoustic properties of speech, although this method is known to be error-prone. New tests assessed the adequacy of linear prediction estimates by using this method to derive synthesis parameters and testing the intelligibility of the synthetic speech that results. Matched sets of sine-wave sentences were created, one set using uncorrected linear prediction estimates of natural sentences, the other using estimates made by hand. Phoneme restrictions imposed on linguistic properties allowed comparisons between continuous and intermittent voicing, oral or nasal and fricative manner, and unrestricted phonemic variation. Intelligibility tests revealed uniformly good performance with sentences created by hand-estimation and a minimal decrease in intelligibility with estimation by linear prediction due to manner variation with continuous voicing. Poorer performance was observed when linear prediction estimates were used to produce synthetic versions of phonemically unrestricted sentences, but no similar decline was observed with synthetic sentences produced by hand estimation. The results show a substantial intelligibility cost of reliance on uncorrected linear prediction estimates when phonemic variation approaches natural incidence.
线性预测是一种广泛应用于分析语音声学特性的技术，但这种方法已知存在误差。新的测试通过使用这种方法来推导合成参数，并测试由此产生的合成语音的可理解性，来评估线性预测估计的充分性。创建了一组匹配的正弦波句子，一组使用未经校正的自然句子的线性预测估计，另一组使用手动估计。对语言属性施加的音位限制允许对连续和间歇发声、口腔或鼻腔和摩擦方式以及不受限制的音位变化进行比较。使用手动估计创建的句子的可理解性测试结果始终良好，由于连续发声方式的变化，线性预测导致的可理解性略有下降。当使用线性预测估计来生成音位不受限制的句子的合成版本时，观察到较差的性能，但使用手动估计生成的合成句子没有观察到类似的下降。结果表明，当音位变化接近自然发生率时，依赖未经校正的线性预测估计会带来相当大的可理解性成本。
