US 12,456,479 B1
Audio playback and software mixer design in DSP with software time-synchronized playback
Tianhe Wu, San Jose, CA (US); Qiao Mu, Beijing (CN); Karthik Raghavan, Sunnyvale, CA (US); and Noah Guengerich, Bellevue, WA (US)
Assigned to AMAZON TECHNOLOGIES, INC., Seattle, WA (US)
Filed by AMAZON TECHNOLOGIES, INC., Seattle, WA (US)
Filed on Nov. 8, 2023, as Appl. No. 18/504,357.
Int. Cl. G10L 21/055 (2013.01); H04B 17/364 (2015.01); H04L 65/80 (2022.01)
CPC G10L 21/055 (2013.01) [H04B 17/364 (2015.01); H04L 65/80 (2013.01)] 20 Claims
OG exemplary drawing
 
1. A device comprising:
a first memory;
an application processor (AP) coupled to the first memory;
a digital signal processor (DSP) coupled to the first memory; and
a speaker coupled to an output of the DSP;
wherein the AP executes instructions to:
determine first playback audio data comprising a first set of frames;
at a first time store the first set of frames in a buffer in the first memory;
determine one or more characteristics associated with operation of the buffer;
determine, based on the one or more characteristics, an estimated playback latency, wherein the estimated playback latency is indicative of an estimated delay in presentation of audio output; and
operate the device based at least in part on the estimated playback latency;
wherein the DSP executes instructions to:
determine second audio data comprising a second set of frames;
retrieve the first set of frames from the buffer at a second time;
generate output data by mixing the first set of frames and the second set of frames; and
send the output data to the speaker.