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排序方式: 共有150条查询结果,搜索用时 31 毫秒
51.
该文提出了一种特征波形提取速率自适应于输入语音帧特性的波形内插编码方案。基于双加权长时预测增益最大原则并利用前向基音判决实现了较为可靠的基音周期估计算法,用基音周期、浊音度和波表面平坦度决定波形提取速率以及SEW(Slowly Evolving Waveform)和REW(Rapidly Evolving Waveform)的更新速率。实验证明,该文提出的波形内插(WI)编码算法相比固定波形提取速率的WI算法在平均码率和计算复杂度上均有一定程度的降低,且合成语音质量明显优于4.8kbps的CELP语音编码算法。 相似文献
52.
高性能汉语语音基音周期估计 总被引:16,自引:3,他引:13
精确度、连续性和可行性是语音基音分析中必须考虑的三个主要问题,为解决这些问题,本文提出一种新的汉语语音基音周期估计方法,首先,我们通过以LVAMDF方法替代AMDF方法获得了更好的基音估计精度和进域分辨度;其次,我们根据汉语语音的特点提出了元音清晰度的概念,在LVAMDF和元音清晰度的基础上,本文设计了元音中心定位、基音谐波单周期校正、基音邻近搜索等一系列算法,从而大大提高了汉语语音基音估计的精确 相似文献
53.
改进汉语数码语音识别中的语音特征提取性能 总被引:3,自引:0,他引:3
汉语数据码语音识别中存在三种与语音特征提取性能有关的语音混淆。 相似文献
54.
Raymond H. Colton 《Journal of voice》1987,1(3)
Pitch is an important attribute of a musical sound. With it the melody of a song is established. With it the beauty of a voice is showcased. But how does pitch affect the perception of voice? Is it used to help to distinguish among voices or does it merely exist in the background, affecting the fine details of a voice but not radically altering the voice? The purpose of this paper is to review some of the evidence on the role of pitch in the perception of voice quality; specifically for the discrimination of one voice quality from another. The objective of the discussion is to understand how pitch affects our perception of voice quality and its importance to the perception of musical sound. 相似文献
55.
Traditionally, timbre has been defined as that perceptual attribute that differentiates two sounds when pitch and loudness are equal and thus is a measure of dissimilarity. By such a definition, each voice possesses a set of timbres, and the identity of any voice or voice category across different pitch-loudness-vowel combinations must be due to an abstraction of the pattern of timbre transformation. Using stimuli produced across the singing range by singers from different voice categories, this study sought to examine how timbre and pitch interact in the perception of dissimilarity. This study also investigated whether listener experience affects the perception of timbre as a function of pitch. The resulting multidimensional scaling (MDS) representations showed that for all stimuli and listeners, dimension 1 correlated with pitch, whereas dimension 2 correlated with spectral centroid and separated vocal stimuli into the categories mezzo-soprano and soprano. Dimension 3 appeared highly idiosyncratic depending on the nature of the stimuli and on the experience of the listener. Inexperienced listeners appeared to rely more heavily on pitch in making dissimilarity judgments than did experienced listeners. The resulting MDS representations of dissimilarity across pitch provide a glimpse of the timbre transformation of voice categories across pitch. 相似文献
56.
57.
Trained singers (TS) generally demonstrate accurate pitch matching, but this ability varies within the general population. Pitch-matching accuracy, given increasing silence intervals of 5, 15, and 25 seconds between target tones and vocal matches, was investigated in TS and untrained individuals. A relationship between pitch discrimination and pitch matching was also examined. Thirty-two females (20–30 years) were grouped based on individual vocal training and performance in an immediate pitch-matching task. Participants matched target pitches following time delays, and completed a pitch discrimination task, which required the classification of two tones as same or different. TS and untrained accurate participants performed comparably on all pitch-matching tasks, while untrained inaccurate participants performed significantly less accurately than the other two groups. Performances declined across groups as intervals of silence increased, suggesting degradation of pitch matching as pitch memory was taxed. A significant relationship between pitch discrimination and pitch matching was revealed across participants. 相似文献
58.
Synthesis and characterization of non-symmetrical liquid crystals containing a cholesteryl ester moiety 总被引:1,自引:0,他引:1
Duo Wei Zhang Wei Huang Guo Hui Pan Wan Li He Yu Bo Cao Jin Bao Guo Hui Cao Huai Yang 《中国化学快报》2009,20(5):562-565
In this paper,a series of chiral non-symmetrical liquid crystals(nBA-chol)consisting of a cholesteryl ester moiety as chiral entity and a biphenyl aromatic core with different terminal alkyl chain has been synthesized and investigated for their liquid crystalline properties.Effects of numbers of methylene units in the terminal alkyl chain on the phase transition temperatures and on the temperature-dependent pitch lengths of the chiral liquid crystals have been studied.The long terminal alkyl chain tends ... 相似文献
59.
Fabrício Lopes Sanchez Sylvio Barbon Júnior Lucimar Sasso Vieira Rodrigo Capobianco Guido Everthon Silva Fonseca Paulo Rogério Scalassara Carlos Dias Maciel José Carlos Pereira Shi-Huang Chen 《Journal of Computational and Applied Mathematics》2009
In this paper we present a new wavelet-based algorithm for low-cost computation of the cepstrum. It can be used for real time precise pitch determination in automatic speech and speaker recognition systems. Many wavelet families are examined to determine the one that works best. The results confirm the efficacy and accuracy of the proposed technique for pitch extraction. 相似文献
60.
本文介绍了后坐模拟试验台俯仰角度控制系统的设计,给出了具体方案设计和软件设计过程。通过控制步进电机经由变速器实现预定俯仰角度控制,连接在俯仰机构上的光电编码器实现俯仰角度的精确检测,据此实现角度俯仰的精确控制。实验结果显示该方案准确、快速、精度高,完全符合系统要求,具有非常大的实用价值。 相似文献