A noise suppresser for the AMR speech codec and evaluation test results based on 3GPP specifications

We propose a noise suppresser (AMR-NS) for the 3GPP standard AMR (adaptive multirate) speech codec. The proposed AMR-NS method is based on spectral subtraction and is structured from spectral amplitude suppression and spectral subtraction that are adaptively controlled by the input signal. The subjective evaluation results based on 3GPP performance requirements (3GPP TS26.077) in a third party testing laboratory show that the proposed AMR-NS has satisfied all the requirements for Japanese and English speech materials. It has also satisfied all the objective evaluation requirements.