Patent ID: 7228272
Filing Date: 2007-06-05
Classification: G10L

Abstract:
1. An apparatus for modifying a speech signal prior to coding the speech signal, the apparatus comprising: a linear prediction coefficient extraction module for receiving a digital speech signal and for producing a set of linear prediction coefficients; an inverse synthesis filter for receiving the digital speech signal and the linear prediction coefficients and for producing a residual signal; a residual modification module for time warping the residual signal based on a continuous linear warp contour selected from the set of all possible warp contours by calculating only a subset of all possible warp contours, whereby a modified residual signal having a regular rather than irregular array of dominant peaks is produced, wherein no portion of any section of the residual is omitted or repeated in the modified residual; and a synthesis filter for receiving the modified residual signal and the linear prediction coefficients for producing a modified digital speech signal suitable for low bit rate coding.