English

Improved Noise Weighting in CELP Coding of Speech - Applying the Vorbis Psychoacoustic Model To Speex

Sound 2016-03-08 v1

Abstract

One key aspect of the CELP algorithm is that it shapes the coding noise using a simple, yet effective, weighting filter. In this paper, we improve the noise shaping of CELP using a more modern psychoacoustic model. This has the significant advantage of improving the quality of an existing codec without the need to change the bit-stream. More specifically, we improve the Speex CELP codec by using the psychoacoustic model used in the Vorbis audio codec. The results show a significant increase in quality, especially at high bit-rates, where the improvement is equivalent to a 20% reduction in bit-rate. The technique itself is not specific to Speex and could be applied to other CELP codecs.

Keywords

Cite

@article{arxiv.1603.01863,
  title  = {Improved Noise Weighting in CELP Coding of Speech - Applying the Vorbis Psychoacoustic Model To Speex},
  author = {Jean-Marc Valin and Christopher Montgomery},
  journal= {arXiv preprint arXiv:1603.01863},
  year   = {2016}
}

Comments

9 pages, Proceedings of the 120th Audio Engineering Society (AES) Convention, Paris, 2006