Estimation of background noise in audio signals

A method of updating background noise estimates in an audio signal, the method comprising:

• computing a first linear prediction gain as a ratio of a residual energy from a first linear prediction to a residual energy from a second linear prediction of a higher order than the first linear prediction for an audio signal segment;
• computing a second linear prediction gain calculated as a ratio of the residual energy from the second linear prediction to residual energy from a third linear prediction of higher order than the second linear prediction for the audio signal segment;
• and
• responsive to a combined metric obtained from a combination of the first and second linear prediction gains satisfying a defined rule, updating a background noise estimate based on the audio signal segment to obtain an updated background noise estimate.

A computer program product comprising a non-transitory computer readable medium storing program code executable by at least one processor to perform operations comprising:

• computing a first linear prediction gain as a ratio of a residual energy from a first linear prediction to a residual energy from a second linear prediction of a higher order than the first linear prediction for an audio signal segment;
• computing a second linear prediction gain calculated as a ratio of the residual energy from the second linear prediction to residual energy from a third linear prediction of higher order than the second linear prediction for the audio signal segment;
• and
• determining whether the audio signal segment comprises a pause based on a combined metric obtained from a combination of the first and second linear prediction gains.

A computer program product comprising a non-transitory computer readable medium storing program code executable by at least one processor to perform operations comprising:

• computing a first linear prediction gain as a ratio of a residual energy from a first linear prediction to a residual energy from a second linear prediction of a higher order than the first linear prediction for an audio signal segment;
• computing a second linear prediction gain calculated as a ratio of the residual energy from the second linear prediction to residual energy from a third linear prediction of higher order than the second linear prediction for the audio signal segment;
• and
• responsive to a combined metric obtained from a combination of the first and second linear prediction gains satisfying a defined rule, updating a background noise estimate based on the audio signal segment to obtain an updated background noise estimate.