Computer Engineering and Applications ›› 2016, Vol. 52 ›› Issue (13): 48-54.

Previous Articles     Next Articles

Design and implementation of parametric stereo encoder in MDFT domain

ZENG Min1,2, TU Weiping1,2, CAI Xufen1,2   

  1. 1.Computer School of Wuhan University, Wuhan 430072, China
    2.National Engineering Research Center for Multimedia Software of Wuhan University, Wuhan 430072, China
  • Online:2016-07-01 Published:2016-07-15


曾  敏1,2,涂卫平1,2,蔡旭芬1,2   

  1. 1.武汉大学 计算机学院,武汉 430072
    2.武汉大学 国家多媒体软件工程技术研究中心,武汉 430072

Abstract: Parametric stereo coding in FFT domain uses different time-frequency transforms in core encoder and stereo parameter extraction module, which leading to high computational load. A parametric stereo codec based on MDFT(Modified Discrete Fourier Transform) is designed and implemented so that the same transform—MDCT(Modified Discrete Cosine Transform) be reused in down mixing channel coding and parameter extraction, thereby computational complexity can be reduced efficiently. Test results show that this codec provides comparable audio quality with the computational complexity reduction by 33% compared to the classical parametric stereo codec in FFT domain. Existing theory of parametric stereo coding in MDFT domain is completed and verified.

Key words: parametric stereo coding, Modified Discrete Fourier Transform(MDFT), time-frequency transform, computational complexity

摘要: FFT域参数立体声编码器在立体声参数提取和主声道编码时采用不同的时频变换, 导致计算复杂度高。设计并实现了一种MDFT(Modified Discrete Fourier Transform,修正离散傅里叶变换)域参数立体声编码器,使得立体声参数提取和主声道编码部分能够复用MDCT(Modified Discrete Cosine Transform,修正离散余弦变换)变换,从而有效降低计算复杂度。与经典的FFT域参数立体声编码器相比,在保证音质相当的同时,编解码计算复杂度下降约33%。完善并验证了已有的MDFT域参数立体声编码理论。

关键词: 参数立体声编码器, 修正离散傅里叶变换(MDFT), 时频变换, 复杂度