Patent ID: 9608588
Date: 2017-03-28
CPC Classifications: H03G

Claim:
1. A method of performing dynamic range control (DRC) with look-ahead on an audio signal, comprising: generating a loudness estimate for the audio signal; generating adaptive time constants by (i) pre-smoothing the loudness estimate, and (ii) analyzing the pre-smoothed loudness estimate during a predefined look-ahead time period by estimating amounts of change in the pre-smoothed loudness estimate over time intervals, respectively, in the predefined look-ahead time period, wherein estimating the amounts of change in the pre-smoothed loudness estimate comprises generating one or more decay slopes for the pre-smoothed loudness estimate and generating one or more rise slopes for the pre-smoothed loudness estimate; smoothing the loudness estimate using the adaptive time constants to produce a shaped loudness estimate; generating DRC gain values to apply to a delayed version of the audio signal based on the shaped loudness estimate; and applying the DRC gain values to the delayed audio signal.