音频压缩编码中参数比特分配算法的研究和实现  

Research and Implementation on Parametric Bit Allocation Algorithm in Audio Compression Coding

作　　者：刘丽[1] 郭立[1] 

机构地区：[1]中国科技大学电子科学与技术系,安徽合肥230026

出　　处：《微电子学与计算机》2008年第2期160-163,共4页Microelectronics & Computer

摘　　要：在分析了参数比特分配的基本原理的基础上,详细讨论了杜比AC-3编码器中参数比特分配算法的实现,对影响编码速度的参数选择部分作了改进,核心比特分配模型参数的快速增益可根据指数编码策略直接确定,信噪比偏移量SNR的计算可采用噪声预测方法估计粗SNR参数,这样使计算得到简化。将此算法应用到杜比AC-3编码器中进行仿真试验,对仿真结果进行主客观评价,显示编码质量令人满意,为杜比AC-3编码器的实时实现奠定了基础。This paper analyses the base theory for the parametric bit allocation algorithm and discusses implementation of bit allocation algorithm of Dolby AC-3 Audio Coder and improved the part of selecting parameter in this algorithm. Fast gain of model parametric of core bit allocation may ascertain direct which base on exponent strategy coding. It make to predigest calculation that adopt prognosticate noise to estimate coarse SNR（ Signal-to-Noise Ratio）parametric. Through computer simulation, the results of performance analyses are given and make objective and subjective assessments. Our simulation demonstrates that coding qualities is satisfactory, and this has established the foundation of Dolby AC-3 encoder real-time realization.

关 键 词：心理声学模型 激励函数 掩蔽曲线 参数比特分配 

分 类 号：TP391[自动化与计算机技术—计算机应用技术]