摘要
为了高效率量化线谱频率(linear spectrumfrequency,LSF)参数,提出了基于G auss ian混合模型(G auss ian m ix ture m ode l,GMM)的LSF量化算法。假设LSF矢量属于GMM中的某一个G auss ian分布,用G auss ian分布随机矢量的量化方法对LSF矢量进行了量化。利用准确的G auss ian分布变量量化误差,得到了G auss ian分布矢量的比特分配方法。应用G auss ian分布随机变量的非均匀量化方法量化每一维LSF参数。最后给出了分裂矢量量化、基于概率密度函数(probab ility dens ityfunction,PDF)量化方法和该算法的性能对比。该无记忆LSF量化算法在21 b/帧可以达到透明量化,比传统Sp litVQ节省3 b。
An efficient linear spectrum frequency (LSF) parameter quantization scheme was developed based on the Gaussian mixture model (GMM). The algorithm assumes that the LSF parameter has a GMM Gaussian distribution so that the LSF vector can be quantized using a random Gaussian distribution vector quantization. The bits of the LSF parameters are allocated according to the precise quantization error of the Gaussian distribution. Each dimension of the LSF parameter is quantized using a non-uniform scalar quantization of the Gaussian distribution variable. Comparison of the method with the Split-VQ and PDF VQ methods shows that the LSF parameters could be transparent quantized at 21 b/frame by the memoryless quantizer, which is 3b less than the conventional Split-VQ method.
出处
《清华大学学报(自然科学版)》
EI
CAS
CSCD
北大核心
2006年第10期1727-1730,共4页
Journal of Tsinghua University(Science and Technology)
基金
国家自然科学基金资助项目(60272020)
关键词
语音编码
矢量量化
Gaussian混合模型
线谱频率
speech coding
vector quantization
Gaussian mixture model (GMM)
linear spectrum frequency (LSF)