Transform Coding Based on Source Filter Model in the MDCT Domain

• Published in: ETRI journal Vol. 35; no. 3; pp. 542 - 545
• Main Author: Ko, Jongmo Sung and Yun‐Ho
• Format: Journal Article
• Language: English
• Published: 한국전자통신연구원 01.06.2013
• Subjects: G.711.1 Annex D; MDCT; Source filter model; transform coding; 전자/정보통신공학
• ISSN: 1225-6463; 2233-7326
• DOI: 10.4218/etrij.13.0212.0368

State‐of‐the‐art voice codecs have been developed to extend the input bandwidth to enhance quality while maintaining interoperability with a legacy codec. Most of them employ a modified discrete cosine transform (MDCT) for coding their extended band. We propose a source filter model‐based coding algorithm of MDCT spectral coefficients, apply it to the ITU‐T G.711.1 super wideband (SWB) extension codec, and subjectively test it to validate the model. A subjective test shows a better quality over the standardized SWB codec.