Audio master selection

Patent metadata

Field	Value
Publication number	US-10754613-B2
Application number	US-201916514280-A
Country	US
Kind code	B2
Filing date	Jul 17, 2019
Priority date	Jul 28, 2003
Publication date	Aug 25, 2020
Grant date	Aug 25, 2020

Abstract

A system is described for maintaining synchrony of operations among a plurality of devices that have independent clocking arrangements. The system includes a task distribution device that distributes tasks to a synchrony group comprising a plurality of devices that are to perform the tasks distributed by the task distribution device in synchrony. The task distribution device distributes each task to the members of the synchrony group over a network. Each task is associated with a time stamp that indicates a time, relative to a clock maintained by the task distribution device, at which the members of the synchrony group are to execute the task. Each member of the synchrony group periodically obtains from the task distribution device an indication of the current time indicated by its clock, determines a time differential between the task distribution device's clock and its respective clock and determines therefrom a time at which, according to its respective clock, the time stamp indicates that it is to execute the task.

First claim

I claim:

1. A method to be performed by a system comprising a first set of network devices, the method comprising:
receiving, by at least one network device in the first set of network devices, a first control instruction for at least a second network device and a third network device to enter into a synchrony group, wherein the first set of network devices comprises:
a first network device comprising a first clock that is configured to provide a first local clock time of the first network device;
the second network device, the second network device comprising a second clock that is configured to provide a second local clock time of the second network device; and
the third network device, the third network device comprising a third clock that is configured to provide a third local clock time of the third network device, wherein the first, second, and third network devices include respective network interfaces that are configured to facilitate network communication between the first, second, and third network devices via one or more data networks,

after receiving, by the at least one network device in the first set of network devices, the first control instruction, selecting, by at least one network device in the first set of network devices, the second network device from among a second set of network devices that comprises the second network device and the third network device, to serve as an audio distributor in the synchrony group comprising the second network device and the third network device;
after selection of the second network device to serve as the audio distributor in the synchrony group:
operating, by the second network device and the third network device, as part of the synchrony group, wherein, while operating as part of the synchrony group, the third network device is configured to:
receive, from the second network device, (a) audio information and (b) playback timing information associated with the audio information, wherein the playback timing information is indicative of at least one future time at which the second network device and the third network device are to engage in synchronized playback of the audio information; and
engage in synchronous playback of the audio information with the second network device based on at least the playback timing information and the third local clock time of the third network device, wherein the first, second, and third local clock times are different during synchronous playback.

2. The method of claim 1 , further comprising:
receiving, by the second network device from the third network device, timing information; and
generating, by the second network device, the playback timing information associated with the audio information using at least the received timing information.

3. The method of claim 2 , wherein the received timing information was generated based on the third clock of the third network device.

4. The method of claim 2 , wherein the system further comprises a fourth network device, and wherein the method further comprises:
operating, by the fourth network device, as part of the synchrony group, wherein, while operating as part of the synchrony group, the fourth network device is configured to:
receive, from the second network device, (a) the audio information and (b) the playback timing information associated with the audio information; and
engage in synchronous playback of the audio information with the second network device based on at least the playback timing information and a fourth local clock time of the fourth network device.

5. The method of claim 4 , further comprising:
while the fourth network device is operating as part of the synchrony group, determining, by the fourth network device, a time differential based on at least the fourth local clock time of the fourth network device, wherein engaging in synchronous playback of the audio information with the second network device based on at least the playback timing information and the fourth local clock time of the fourth network device comprises engaging in synchronous playback of the audio information with the second network device based on at least the playback timing information, the fourth local clock time of the fourth network device, and the determined time differential.

6. The method of claim 2 , wherein the system further comprises a fourth network device, and wherein the method further comprises:
sending, by the fourth network device, to the at least one network device in the first set of network devices, the first control instruction.

7. The method of claim 1 , wherein the system further comprises a fourth network device, and wherein the method further comprises:
receiving, from the fourth network device by a given one of the second network device or the third network device, a first volume control instruction for the synchrony group; and
after receiving the first volume control instruction for the synchrony group, the given one of the second network device or the third network device:
adjusting a respective volume level of the given one of the second network device or the third network device based on the received first volume control instruction; and
sending, to the other of the second network device or the third network device, a second volume control instruction based on the received first volume control instruction.

8. The method of claim 1 , wherein selecting the second network device from among the second set of network devices to serve as the audio distributor comprises:
selecting the second network device from among the second set of network devices based on at least one of (1) a load of one or more network devices and (2) a network latency.

9. The method of claim 1 , wherein selecting the second network device from among the second set of network devices comprises:
selecting the second network device from among the second set of network devices based on at least a network performance metric of the second network device.

10. The method of claim 1 , further comprising:
while the third network device is operating as part of the synchrony group, receiving, by the third network device from the second network device, clock timing information comprising an indication of the second local clock time of the second network device.

11. A tangible, non-transitory computer-readable medium comprising instructions that, when executed by a system comprising a first set of network devices, perform functions comprising:
receiving, by at least one network device in the first set of network devices, a first control instruction for at least a second network device and a third network device to enter into a synchrony group, wherein the first set of network devices comprises:
a first network device comprising a first clock that is configured to provide a first local clock time of the first network device;
the second network device, the second network device comprising a second clock that is configured to provide a second local clock time of the second network device; and
the third network device, the third network device comprising a third clock that is configured to provide a third local clock time of the third network device, wherein the first, second, and third network devices include respective network interfaces that are configured to facilitate network communication between the first, second, and third network devices via one or more data networks,

after receiving, by the at least one network device in the first set of network devices, the first control instruction, selecting, by at least one network device in the first set of network devices, the second network device from among a second set of network devices that comprises the s

Assignees

• Sonos Inc
• Sonos Inc

Inventors

• Millington Nicholas A J

Classifications

• H04L65/75

  Media network packet handling · CPC title

• H04L65/613

  for the control of the source by the destination (control signals issued by the client directed to the server or network components specially adapted for selective content distribution H04N21/637) · CPC title

• H04L65/61

  for supporting one-way streaming services, e.g. Internet radio · CPC title

• H04L67/55

  Push-based network services · CPC title

• H04L65/611

  for multicast or broadcast (systems for broadcast or conference H04L12/18; arrangements for broadcast or distribution combined with broadcast H04H20/00; arrangements for broadcast applications with a direct linkage to broadcast information or to broadcast space-time H04H60/00; selective distribution of broadcast services, e.g. multimedia broadcast multicast service [MBMS], H04W4/06) · CPC title