High Quality Speech Coding using Combined Parametric and Perceptual Modules

A novel approach to speech coding using the hybrid architecture is presented. Advantages of parametric and perceptual coding methods are utilized together in order to create a speech coding algorithm assuring better signal quality than in traditional CELP parametric codec. Two approaches are discussed. One is based on selection of voiced signal components that are encoded using parametric algorithm, unvoiced components that are encoded perceptually and transients that remain unencoded. The second approach uses perceptual encoding of the residual signal in CELP codec. The algorithm applied for precise transient selection is described. Signal quality achieved using the proposed hybrid codec is compared to quality of some standard speech codecs.

• M. Kulesza
• G. Szwoch
• A. Czyżewski

• CELP residual coding
• hybrid codec architecture
• perceptual speech coding
• speech codecs comparison.

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