AC-3数字音频压缩中的变换编码算法

Transform Coding Algorithm of AC-3 Digital Audio Compression

变换编码是音频压缩中的一个重要部分,文中叙述了AC-3数字音频压缩标准中的变换编码技术,包括改进离散余弦变换和反变换(MDCT和IMDCT)、时域混叠抵消与自适应窗选择,详细推导了用于MDCT和IMDCT的递归算法。

Transform coding is an important part of audio compression. In this article, the author presents the transform coding technique of AC-3 digital oudio compression standard, which includes modified discrete cosine transform and its inverse transform （MDCT ＆ IMDCT）, tine domain aliasing cancellation （TDAC） and adaptive window selection. The derivation of recursive architecture for MDCT and IMDCT is given in detail.