English

PostGAN: A GAN-Based Post-Processor to Enhance the Quality of Coded Speech

Audio and Speech Processing 2022-02-01 v1 Sound

Abstract

The quality of speech coded by transform coding is affected by various artefacts especially when bitrates to quantize the frequency components become too low. In order to mitigate these coding artefacts and enhance the quality of coded speech, a post-processor that relies on a-priori information transmitted from the encoder is traditionally employed at the decoder side. In recent years, several data-driven post-postprocessors have been proposed which were shown to outperform traditional approaches. In this paper, we propose PostGAN, a GAN-based neural post-processor that operates in the sub-band domain and relies on the U-Net architecture and a learned affine transform. It has been tested on the recently standardized low-complexity, low-delay bluetooth codec (LC3) for wideband speech at the lowest bitrate (16 kbit/s). Subjective evaluations and objective scores show that the newly introduced post-processor surpasses previously published methods and can improve the quality of coded speech by around 20 MUSHRA points.

Keywords

Cite

@article{arxiv.2201.13093,
  title  = {PostGAN: A GAN-Based Post-Processor to Enhance the Quality of Coded Speech},
  author = {Srikanth Korse and Nicola Pia and Kishan Gupta and Guillaume Fuchs},
  journal= {arXiv preprint arXiv:2201.13093},
  year   = {2022}
}

Comments

Accepted to ICASSP 2022

R2 v1 2026-06-24T09:10:19.732Z