3 results about "Comfort noise" patented technology

A method and device are implemented in a multi-channel sound decoder for injecting multi-channel comfort noise in a decoded multi-channel sound signal. Background noise in a decoded mono down-mixed signal is estimated, and comfort noise for each of a plurality of channels of the decoded multi-channel sound signal is calculated in response to the estimated background noise. The calculated comfort noise is injected in the respective channels of the decoded multi-channel sound signal.

Enabling generation of comfort noise in an encoder using an estimated coherence parameter in a network using a discontinuous transmission, DTX, includes receiving time domain audio input comprising audio input signals; and processing the input signals on a frame-by-frame basis by: encoding active content of each input signal at a first bit rate until an inactive period is detected in the input signals; switching the encoding from the active encoding to inactive encoding to encode background noise at a second bit rate during the inactive period; estimating coherence parameters during the inactive period based on a low-pass filtering or averaging of cross-spectra including reinitializing a low pass filter state of the cross-spectra based on a coherence parameter from a previous inactive period; encoding the coherence parameters estimated; and initiating transmitting of the encoded active content, background noise, and coherence parameters towards a decoder.

A method and a transmitting node for supporting generation of comfort noise for at least two audio channels at a receiving node. The method is performed by a transmitting node. The method comprises determining spectral characteristics of audio signals on at least two input audio channels and determining a spatial coherence between the audio signals. The spatial coherence is associated with perceptual importance measures. A compressed representation of the spatial coherence is determined per frequency band by weighting the spatial coherence within each frequency band according to the perceptual importance measures. Information about the spectral characteristics and the compressed representation of the spatial coherence per frequency band is signaled to the receiving node for enabling the generation of the comfort noise at the receiving node.