Audio Decoder Having A Bandwidth Extension Module With An Energy Adjusting Module

摘要

An audio decoder configured to produce an audio signal from a bitstream containing audio frames includes: a core band decoding module configured to derive a directly decoded core band audio signal from the bitstream; a bandwidth extension module configured to derive a parametrically de-coded bandwidth extension audio signal from the core band audio signal and from the bitstream, wherein the bandwidth extension audio signal is based on a frequency domain signal having at least one frequency band; and a combiner configured to combine the core band audio signal and the bandwidth extension audio signal so as to produce the audio signal; wherein the bandwidth extension module includes an energy adjusting module being configured in such way that in a current audio frame in which an audio frame loss occurs, an adjusted signal energy for the cur-rent audio frame for the at least one frequency band is set.

主权项

1. An audio decoder configured to produce an audio signal from a bitstream comprising audio frames, the audio decoder comprising:
a core band decoding module configured to derive a directly decoded core band audio signal from the bitstream; a bandwidth extension module configured to derive a parametrically decoded o bandwidth extension audio signal from the core band audio signal and from the bitstream, wherein the bandwidth extension audio signal is based on a frequency domain signal comprising at least one frequency band; and a combiner configured to combine the core band audio signal and the bandwidth extension audio signal so as to produce the audio signal; wherein the bandwidth extension module comprises an energy adjusting module being configured in such way that in a current audio frame in which an audio frame loss occurs, an adjusted signal energy for the current audio frame for the at least one frequency band is set based on a current gain factor for the current audio frame, wherein the current gain factor is derived from a gain factor from a previous audio frame or from the bitstream, and based on an estimated signal energy for the at least one frequency band, wherein the estimated signal energy is derived from a spectrum of the current audio frame of the core band audio signal.