Patent ID: 9715883
Date: 2017-07-25
CPC Classifications: G10L

Claim:
1. A CELP encoder comprising a linear prediction analyzer configured to generate linear prediction filter coefficients for a current frame of an audio content and encode the linear prediction filter coefficients into a bitstream; an excitation generator configured to determine a current excitation of the current frame as a combination of an adaptive codebook excitation and an innovation codebook excitation, which, when filtered by a linear prediction synthesis filter based on the linear prediction filter coefficients, recovers the current frame, by constructing the adaptive codebook excitation defined by a past excitation and an adaptive codebook index for the current frame and encoding the adaptive codebook index into the bitstream; and constructing the innovation codebook excitation defined by an innovation codebook index for the current frame and encoding the innovation codebook index into the bitstream; and an energy determiner configured to determine an energy of a version of the audio content of the current frame filtered a weighting filter, to acquire a global gain value and encoding the global gain value into the bitstream, the weighting filter construed from the linear prediction filter coefficients.