Efficient Algorithms for MPEG-4 AAC-ELD, AAC-LD and AAC-LC Filterbanks
Recently MPEG has developed a new audio coding standard -MPEG-4 AAC Enhanced Low Delay (ELD), targeting low bit rate, full-duplex communication applications such as audio and video conferencing. The AAC-ELD combines low delay SBR filterbank with a low delay core coder filterbank to achieve both high coding efficiency and low algorithmic delay. In this paper, we propose an efficient mapping of the AAC-ELD core coder filterbank to the well known MDCT. This provides a fast algorithm for the new filterbank. Since AAC-LD and AAC-LC profiles also use MDCT filterbank, this mapping enables efficient joint implementation of filterbanks for all 3 profiles. We also present a very efficient 15-point DCT-II algorithm that is useful for implementation of all 3 profiles with frame lengths of 960 and 480. This algorithm requires just 17 multiplications and 67 additions. The overall design structure and complexity analysis of proposed implementation of the filterbanks is also provided.
Ravi K.Chivukula Yuriy A.Reznik Venkat Devarajan
The University of Texas at Arlington Stanford University
国际会议
2008 International Conference on Audio，Language and Image Processing(2008国际声音、语言、图像过程大会)
镇江
英文
1629-1634
2008-07-07（万方平台首次上网日期，不代表论文的发表时间）