可变码率压缩和音速、音调调整的音频信号的正弦模型(英文)  

Compact Sinusoidal Representations of Audio for Scalable Compression and Time/Pitch-Scale Modifications

作　　者：Al-MoussawyRaed 尹俊勋[1] 宋少鹏[1] 

机构地区：[1]华南理工大学电子与信息学院,广东广州510640

出　　处：《华南理工大学学报（自然科学版）》2003年第7期22-27,共6页Journal of South China University of Technology(Natural Science Edition)

基　　金：国家自然科学基金(69820007);广东省自然科学基金(011611)~~

摘　　要：提出一种用于可变码率音频编码的正弦+噪声(SN)模型。提出了对正弦模型进行本质上的增强。从大、中、小三个前后衔接的尺度上对音频信号进行时域重叠相加(overlap-add)的正弦分析时引入了心理声学模型加权的匹配跟踪算法(matching pursuits algorithm),将大尺度正弦分析-合成后的余量送入相对小的尺度进行分析,以达到相应的分辨率。这种算法有效的解决了正弦模型固有的预回声效应,提高了重建音频的质量。这一模型适用于可变码率、高保真的音频压缩和发音速度、音调的调整。This paper presents a signal model for scalable perceptual audio coding consisting of Sines + Noise (SN) representations. The paper essentially presents a fundamental enhancement to the sinusoidal modeling component. The enhancement involves an audio signal scheme based on carrying out overlap-add sinusoidal modeling at three successive time scales, large, medium, and small. The sinusoidal modeling is done in an analysis-by-synthesis overlap-add manner across the three scales by using a psychoacoustically based matching pursuits. The sinusoidal modeling residual at the first scale is passed to a couple of smaller scales to allow for modeling of various signal features at appropriate resolutions. This approach greatly helps to correct the pre-echo inherent in the sinusoidal model. The new scheme gives an improved perceptual audio quality compared to our previous work while using the same number of sinusoids.

关 键 词：多分辨率正弦模型 参数音频编码 低码率音频编码 信号调整 

分 类 号：TN912.32[电子电信—通信与信息系统]