Patent ID: 9431982
Filing Date: 2016-08-30
CPC Classification: H03G

Claim Text:
1. A method adaptively adjusting audio output levels in a multi-channel audio system, comprising: receiving a first plurality of audio signals including a first left-channel audio signal and a first right-channel audio signal; receiving a first gain specified by a volume control of the audio system; applying the first gain to the first plurality of audio signals, producing a volume-adjusted plurality of audio signals including a volume-adjusted left-channel audio signal and a volume-adjusted right-channel audio signal; delaying the volume-adjusted plurality of audio signals, producing a delayed volume-adjusted plurality of audio signals; determining a first volume change corresponding to a difference between the first gain at a first time and the first gain at a second time, wherein the second time is after the first time and the first volume change indicates a decrease in volume; comparing a plurality of volume changes including the first volume change and at least one past volume change to determine that a majority of the plurality of volume changes correspond to increases of the first gain; determining a left-channel loudness level of the volume-adjusted left-channel audio signal at the second time; determining a right-channel loudness level of the volume-adjusted right-channel audio signal at the second time; combining the left-channel loudness level and the right-channel loudness level, producing a combined loudness level; determining that the combined loudness level is to be boosted to expand dynamic range as a result of the majority of the plurality of volume changes corresponding to increases of the first gain; determining a second gain to boost the combined loudness level; applying the second gain to the delayed volume-adjusted plurality of audio signals to create a second plurality of audio signals; and outputting the second plurality of audio signals.