Patent ID: 7307981
Filing Date: 2007-12-11
Classification: G10L

Abstract:
1. An apparatus for converting voice packets transmitted/received through a network comprising: a first transcoder which performs at least one of bit-unpacking or unquantization on a first encoded packet to obtain a first line spectral pair (LSP) parameter of a first encoder, and which converts the first LSP parameter to a second parameter of a second encoder; and a second transcoder which performs at least one of bit-unpacking or unquantization on a second encoded packet to obtain a third LSP parameter of the second encoder, and which converts and unquantizes the third LSP parameter to a fourth LSP parameter of the first encoder, wherein the first transcoder includes a first LSP parameter converting circuit which comprises: an LSP interpolating circuit to perform interpolation between frames on the first LSP parameter, said LSP interpolating circuit multiplying the first LSP parameter of a previous frame by an interpolation constant and multiplying the first LSP parameter of a present frame by a value obtained by subtracting the interpolation constant from a maximum interpolation constant; and a multiplier to multiply the interpolated LSP parameter by a constant to compensate for a scale difference of LSP and to output the second LSP parameter based on a result of said multiplication.