基于核Fisher判别和加权码书映射的音频信号削波修复方法

本文基于核Fisher判别（Kernel Fisher Discriminant, KFD）和加权码书映射（Weighted Codebook Mapping, WCBM），提出了一种MDCT（Modified Discrete Cosine Transform）域的音频信号削波修复方法。首先根据音频信号的MDCT系数提取子带包络等四种削波特征参数；其次，利用这些特征参数训练检测音频信号出现削波的核Fisher分类器；最后，利用子带包络的WCBM来修复音频信号的削波。测试结果表明，本文所提方法能有效修复音频信号的削波，其性能优于现有的几种削波修复方法。

Clipping restoration of audio signals based on kernel Fisher discriminant and weighted codebook mapping

In this paper, the clipping restoration of audio signals based on kernel Fisher discriminant (KFD) and the weighted codebook mapping (WCBM) in Modified Discrete Cosine Transform (MDCT) domain is proposed. First, the four clipping features are extracted according to the MDCT coefficients of audio signals. Second, the clipping feature parameters are used to train the optimal kernel Fisher classifier which is employed to detect the clipping. Finally, the WCBM of sub-band envelop is adopted to restore the clipping of audio signals. The test results indicate that the proposed algorithm can effectively remove the clipping distortion of audio signals and obviously outperforms the existing clipping restoration methods.