Patent ID: 6304847
Filing Date: 2001-10-16
Classification: G10L

Abstract:
A method for dual-mode audio decoding using an Inverse Modified Discrete Cosine Transform, comprising:receiving a bit stream;identifying the received bit stream as an AC-3 or an MPEG bit stream;forming an AC-3 sequence if an AC-3 bit stream is received;multiplying the AC-3 sequence by a predetermined pre-twiddling factor;performing an inverse fast Fourier transform on the pre-twiddled AC-3 sequence to generate an AC-3 function;multiplying the AC-3 function by a predetermined post-twiddling factor;forming an MPEG sequence if an MPEG bit stream is received;performing a fast Fourier transform on the MPEG sequence to generate an MPEG function;multiplying the MPEG function by a predetermined twiddling factor; andrearranging the twiddled MPEG function.