一种低码率移动通信音频带宽扩展方法研究

A Research of a Low Bit Rate Audio Bandwidth Extension Method for Mobile Communication

在移动通信中,音频编解码器要求采用计算复杂度低、码率低并且高质量的音频编码算法.提出了一种新的低码率音频带宽扩展算法,利用码本映射法得到高频合成滤波器系数,编码端在复用码流中高频部分只传递量化的增益修正,从而只增加极少的编码比特数和运算复杂度即可重建高频分量,提高解码音质.

A good audio codee for mobile communication should provide high quality with low bit rate and low computational complexity. This paper proposed a novel low bit rate audio coding bandwidth extension method, which can improve decoded audio quality with inoreasing only a few coding bits per frame and a little computational complexity. This method calculate high-frequency synthesis filter by using codebook mapping method, and transmit only quantified gain corrections in high - frequency part of multiplexing coding bit stream.