摘要
本文将基音周期波形(PCW)在时间方向上逐个相位对齐,提出了一种新的线性预测残差(LPR)域典型波形(PW)提取和块内插方法。该方法可以避免内插后的PCW分界处的不连续而引起的听觉上的失真,同时也使得PW分界的选择不至于太严格。借助于这种PW提取和块内插方法,本文实现了一种2.4 kb/s线性预测编码方案,计算机模拟结果表明,该方案得到的重建语音与4.8 kb/s码激励线性预测算法接近。
A new method of prototype waveform extraction and blockwise interpolation in Linear Predictive Residual(LPR) domain was suggested by aligning phase of Pitch-Cycle Wave-form(PCW) along the time axis one by one. This method may avoid the perceptual distortion due to discontinuities near boundaries of interpolated pew. At the same time, it made the boundary selection of Prototype Waveform(PW) not too strict. A novel 2.4 kb/s Linear Predictive Coding(LPC) model was established based on this extraction and blockwise interpolation of PW. The computer simulation results show that the reconstructed speech quality with this model closed to Code-Excited Linear Predictive(CELP) algorithm at 4.8 kb/s.
基金
国家自然科学基金(69872005)
北京市跨世纪人才工程专项基金
北京市科技新星基金
关键词
语音编码
线性预测
波形内插
矢量量化
Speech coding, Linear prediction, Waveform interpolation, Vector quantization
