Patent ID: 11894006
Assignee: DOLBY LABORATORIES LICENSING CORPORATION
Field: Computer technology (Electrical engineering)
Classification: CPC G  H | IPC G

Claim 11:
12. A method of processing an audio signal, comprising:
receiving audio from a playback volume controller/leveler;
computing a threshold level dynamically using a minimum-follower mechanism over a history of observed audio signals by:
computing a frequency spectrum of the audio, the frequency spectrum having a plurality of subbands;
computing an average minimum energy across the subbands over time; and
computing the threshold level based at least in part on the average minimum energy;

comparing a level of the audio with the threshold level;
in accordance with the level being greater than the threshold level,
processing the audio in accordance with a first dynamic range control (DRC) compression curve, the first DRC compression curve indicating a first amount of gain to apply to the audio;

in accordance with the level being less than or equal to the threshold level,
processing the audio in accordance with a second DRC compression curve, the second DRC compression curve indicating a second amount of gain to apply to the audio, wherein the second amount of gain is different than the first amount of gain; and

sending the audio to a downstream device.