Playback Device

Patent metadata

Field	Value
Publication number	US-2023367541-A1
Application number	US-202218146264-A
Country	US
Kind code	A1
Filing date	Dec 23, 2022
Priority date	Jul 28, 2003
Publication date	Nov 16, 2023
Grant date	—

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

What is claimed as new and desired to be secured by Letters Patent of the United States is:

1 . A computing device comprising:
one or more processors; and tangible, non-transitory computer-readable media comprising program instructions stored therein, wherein the program instructions are executable by the one or more processors such that the computing device is configured to: operate in a first mode in which the computing device is serving as an audio information channel device for an individual zone player, wherein the individual zone player is configured to play first audio content in a standalone mode; receive an indication that the computing device is to begin serving as an audio information channel device for a synchrony group that comprises at least a first zone player and a second zone player that are communicatively coupled with the computing device over an asynchronous data network configured to exchange digital data packets, wherein the computing device, the first zone player, and the second zone player each have a different respective clock time; after receiving the indication that the computing device is to begin serving as the audio information channel device for the synchrony group,
(a) configure the synchrony group to playback audio in synchrony, wherein configuring the synchrony group comprises sending control information to at least one of the first zone player or the second zone player that instructs the at least one of the first zone player or the second zone player to begin operating as part of the synchrony group; and
(b) transition from operating in the first mode to operating in a second mode in which the computing device serves as the audio information channel device for the synchrony group, wherein, while operating in the second mode, the computing device is configured to:
exchange, via the asynchronous data network, clock timing information with each of the first zone player and the second zone player that facilitates time synchronization between the computing device and each of the first zone player and the second zone player, wherein the time synchronization establishes a common notion of clock time for each of the first zone player, the second zone player, and the computing device;
generate playback timing information associated with second audio content to be played by the synchrony group, wherein the playback timing comprises an indicator of a first future time, relative to the common notion of clock time, at which at least the first and second zone players are to initiate synchronous playback of the second audio content; and
transmit, via a network interface to the first and second zone players over the asynchronous data network, both (a) the audio information representing the second audio content and (b) the playback timing information, thereby enabling the first and second zone players to play back the second audio content in synchrony.

2 . The computing device of claim 1 , wherein while operating in the second mode, the computing device is configured to obtain the second audio content to be played by the synchrony group from an audio source separate from the computing device, the first zone player, or the second zone player, wherein the audio source comprises from one of (a) a network-accessible audio source that is communicatively coupled to the computing device over one or both of a local area network (LAN) or a wide area network (WAN), (b) a local audio source that is directly connected to the computing device, or (c) a storage medium associated with the computing device.

3 . The computing device of claim 1 , wherein the program instructions that are executable by the one or more processors such that the computing device is configured to transmit the audio information to the first and second zone players over the asynchronous data network comprise program instructions that are executable by the one or more processors such that the computing device is configured to:
transmit a series of frames, wherein individual frames comprise audio information representing a respective portion of the second audio content, wherein the first future time corresponds to a first frame in the series of frames, and wherein the playback timing information further comprises, for an individual subsequent frame after the first frame in the series of frames, an indicator of a respective future time, relative to the clock time of the computing device, at which the respective portion of the second audio content in the individual subsequent frame is to be synchronously played back by the first and second zone players.

4 . The computing device of claim 1 , wherein the program instructions that are executable by the one or more processors such that the computing device is configured to generate the playback timing information for the audio information comprise program instructions that are executable by the one or more processors such that the computing device is configured to:
capture a reading of the clock time of the computing device; calculate the first future time by adding a time delay to the captured reading of the clock time; and generate a timestamp that indicates the first future time.

5 . The computing device of claim 1 , further comprising program instructions stored on the tangible, non-transitory computer-readable medium that are executable by the one or more processors such that the computing device, while operating as the audio information channel device for the synchrony group, is configured to:
while the first and second zone players are playing back the second audio content in synchrony, receive a request for the synchrony group to switch from playing back the second audio content to playing back new audio content; and in response to receiving the request for the synchrony group to switch from playing back the second audio content to playing back the new audio content:
transmit, to the first and second zone players over the asynchronous data network, a command to terminate playback of the second audio content;
generate playback timing information associated with the new audio content that comprises an indicator of a second future time, relative to the clock time of the computing device, at which the first and second zone players are to initiate synchronous playback of the new audio content; and
transmit the playback timing information associated with the new audio content and audio information representing the new audio content to the first and second zone players over the asynchronous data network and thereby cause the first and second zone players to play back the new audio content in synchrony.

6 . The computing device of claim 1 , wherein the computing device comprises a zone player.

7 . The computing device of claim 1 , wherein the program instructions that are executable by the one or more processors such that the computing device is configured to receive the indication that the computing device is to begin operating as an audio information channel device for the synchrony group comprise program instructions that are executable by the one or more processors such that the computing device is configured to:
receive a request to begin operating as the audio information channel device for the synchrony group from (a) a controller device, (b) one of the first zone player or the second zone player, (c) another network device, or (d) a user.

8 . The computing device of claim 1 , wherein while in the first mode, the computing device is configured to (a) obtain the first audio content and (b) play back at least a first portion of the obtained first audio content.

9 . The computing device of claim 1 , further comprising program instructions that are executable by the one or more proces

Assignees

• Sonos Inc

Inventors

• Millington Nicholas A J

Classifications

• G06F3/165 Primary

  Management of the audio stream, e.g. setting of volume, audio stream path · CPC title

• H04N21/43615

  Interfacing a Home Network, e.g. for connecting the client to a plurality of peripherals (home Audio Video Interoperability [HAVI] data switching networks H04L12/2805) · CPC title

• H04L65/80

  Responding to QoS · CPC title

• H04L69/28

  Timers or timing mechanisms used in protocols · CPC title

• G06F16/60

  of audio data · CPC title