US 12,353,790 B1
Method and system for time-aligned audio playback
Stephen E. Pinto, Mountain View, CA (US); and Yasser Rihan, Redwood City, CA (US)
Assigned to Apple Inc., Cupertino, CA (US)
Filed by Apple Inc., Cupertino, CA (US)
Filed on Sep. 17, 2021, as Appl. No. 17/478,712.
Claims priority of provisional application 63/083,784, filed on Sep. 25, 2020.
Int. Cl. G06F 3/16 (2006.01); G06F 3/01 (2006.01); G06T 19/00 (2011.01); H04J 3/06 (2006.01); H04L 7/00 (2006.01); H04R 3/12 (2006.01)
CPC G06F 3/165 (2013.01) [G06F 3/011 (2013.01); G06T 19/006 (2013.01); H04J 3/0667 (2013.01); H04L 7/0008 (2013.01); H04R 3/12 (2013.01)] 20 Claims
OG exemplary drawing
 
1. A method performed by a first electronic device that has an internal clock, the method comprising:
sharing a clock in the first electronic device with a second electronic device by:
determining whether the first electronic device is within a threshold distance from the second electronic device,
responsive to the first electronic device being within the threshold distance, transmitting clock synchronization messages based on the clock in the first electronic device to the second electronic device, and
responsive to the first electronic device not being within the threshold distance, transmitting a message to instruct the second electronic device to request time information from a remote server to set a clock of the second electronic device such that both electronic devices are configured to operate using their separate clocks that are synchronized with a clock of the remote server;
generating timebase information that includes a first timebase that defines a first relationship between the shared clock and the internal clock of the first electronic device and a second timebase that defines a second relationship between the first timebase and a playback state of audio content;
transmitting the timebase information to the second electronic device; and
synchronously playing back the audio content on the first electronic device with playback of the audio content on the second electronic device according to the first and second relationships defined by the first and second timebases, respectively, of the timebase information.