IMPROVED CODING TECHNIQUES USING ESTIMATED SPECTRAL MAGNITUDE AND PHASE DERIVED FROM MDCT COEFFICIENTS

摘要

Estimates of spectral magnitude and phase are obtained by an estimation process using spectral information from analysis filter banks such as the Modified Discrete Cosine Transform. The estimation process may be implemented by convolution-like operations with impulse responses. Portions of the impulses responses may be selected for use in the convolution-like operations to trade off between computational complexity and estimation accuracy. Mathematical derivations of analytical expressions for filter structures and impulse responses are disclosed.