Abstract: The invention provides an audio decoder being configured for decoding a bitstream so as to produce therefrom an audio output signal, the bitstream including at least an active phase followed by at least an inactive phase, wherein the bitstream has encoded therein at least a silence insertion descriptor frame which describes a spectrum of a background noise, the audio decoder including: a silence insertion descriptor decoder configured to decode the silence insertion descriptor frame; a decoding device configured to reconstruct the audio output signal from the bitstream during the active phase; a spectral converter configured to determine a spectrum of the audio output signal; a noise estimator device configured to determine a first spectrum of the noise of the audio output signal; a resolution converter configured to establish a second spectrum of the noise of the audio output signal; a comfort noise spectrum estimation device; and a comfort noise generator.

Abstract: The spectral domain is efficiently used in order to parameterize the background noise using a background noise estimator configured to determine a parametric background noise estimate based on a spectral decomposition representation of an input audio signal so that the parametric background noise estimate spectrally describes a spectral envelope of a background noise of the input audio signal, thereby yielding a background noise synthesis which is more realistic and thus leads to a more transparent active to inactive phase switching.

Abstract: The spectral domain is efficiently used in order to parameterize the background noise thereby yielding a background noise synthesis which is more realistic and thus leads to a more transparent active to inactive phase switching.