Estimation of background noise in audio signals

An apparatus for updating a background noise estimate of an audio signal, the apparatus comprising:

• at least one processor;
• and
• at least one memory storing computer readable instructions executed by the at least one processor to perform operations comprising:
• computing at least one parameter associated with an audio signal segment that is among a plurality of audio signal segments of the audio signal, based on both of:
• a first linear prediction gain calculated as a quotient between a residual energy from a first linear prediction and a residual signal energy from a second linear prediction for the audio signal segment, the second linear prediction being from a higher order than the first linear prediction;
• and
• a second linear prediction gain calculated as a quotient between the residual signal energy from the second linear prediction and a residual signal energy from a third linear prediction for the audio signal segment, the third linear prediction being from a higher order than the second linear prediction;
• determining whether the audio signal segment comprises a pause, based at least on the at least one parameter;
• and
• responsive to when the audio signal segment is determined to comprise a pause, 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 storage medium storing instructions which, when executed on at least one processor, cause the at least one processor to perform operations comprising:

• computing at least one parameter associated with an audio signal segment that is among a plurality of audio signal segments of the audio signal, based on both of:
• a first linear prediction gain calculated as a quotient between a residual energy from a first linear prediction and a residual signal energy from a second linear prediction for the audio signal segment, the second linear prediction being from a higher order than the first linear prediction;
• and
• a second linear prediction gain calculated as a quotient between the residual signal energy from the second linear prediction and a residual signal energy from a third linear prediction for the audio signal segment, the third linear prediction being from a higher order than the second linear prediction;
• determining whether the audio signal segment comprises a pause, based at least on the at least one parameter;
• responsive to when the audio signal segment is determined to comprise a pause, updating a background noise estimate based on the audio signal segment to obtain an updated background noise estimate.