Media Playback Device and System

Patent metadata

Field	Value
Publication number	US-2020379723-A1
Application number	US-202016999048-A
Country	US
Kind code	A1
Filing date	Aug 20, 2020
Priority date	Jul 28, 2003
Publication date	Dec 3, 2020
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 is:

1 . A computing device comprising:
a network interface; a clock that is configured to provide a clock time of the computing device; at least one processor; a tangible, non-transitory computer-readable medium; and program instructions stored on the tangible, non-transitory computer-readable medium that, when executed by the at least one processor, cause the computing device to perform functions comprising:
operating in a first mode in which the computing device is not serving as an audio information channel device for any synchrony group;
receiving an indication that the computing device is to begin serving as an audio information channel device for a synchrony group that comprises at least first and second zone players 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,
(a) configuring 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 second zone player that (i) identifies the computing device as the audio information channel device for the synchrony group, (ii) initiates establishment of at least one communication channel by which audio information will be transmitted by the audio information channel device to the synchrony group, and (iii) instructs the at least one of the first zone player or second zone player to begin operating as part of the synchrony group; and
(b) transitioning 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;
obtain given audio content to be played back by the synchrony group;
generate playback timing information associated with the given audio content that 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 given audio content; and
transmit, via the network interface to the first and second zone players over the asynchronous data network, both (a) the audio information representing the given audio content via the at least one communication channel, and (b) the playback timing information, thereby enabling the first and second zone players to play back the given audio content in synchrony.

2 . The computing device of claim 1 , wherein:
while in the first mode, the computing device operates as a playback device that is configured to play back audio content.

3 . The computing device of claim 1 , wherein receiving the indication that the computing device is to begin operating as an audio information channel device for the synchrony group comprises:
receiving 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 and second zone players, (c) another network device, or (d) a user.

4 . The computing device of claim 1 , wherein:
while in the first mode, the computing device operates as a playback device that is configured to (a) obtain audio content and (b) play back at least a first portion of the obtained audio content, wherein the given audio content transmitted while operating in the second mode comprises at least a second portion of the audio content obtained while operating in the first mode.

5 . The computing device of claim 1 , further comprising program instructions stored on the tangible, non-transitory computer-readable medium that, when executed by the at least one processor, cause the computing device, while operating as the audio information channel device for the synchrony group, to perform functions comprising:
receiving a request for the synchrony group to play back the given audio content, wherein the given audio content is obtained in response to receiving the request for the synchrony group to play back the given audio content.

6 . The computing device of claim 1 , wherein transmitting the audio information to the first and second zone players over the asynchronous data network comprises:
transmitting a first portion of the audio information to the first and second zone players over the asynchronous data network before synchronous playback of the given audio content begins and transmitting a second portion of the audio information to the first and second zone players over the asynchronous data network after synchronous playback of the given audio content begins.

7 . The computing device of claim 1 , wherein transmitting the playback timing information and the audio information to the first and second zone players over the asynchronous data network comprises:
transmitting the playback timing information in a separate communication from the audio information.

8 . The computing device of claim 1 , wherein establishment of the at least one communication channel by which audio information will be transmitted comprises establishment of at least one first communication channel by which audio information will be transmitted, and wherein sending the control information to at least one of the first zone player or second zone player further comprises sending control information to at least one of the first zone player or second zone player that initiates establishment of at least one second communication channel by which the clock timing information will be transmitted by the computing device.

9 . The computing device of claim 1 , further comprising program instructions stored on the tangible, non-transitory computer-readable medium that, when executed by the at least one processor, cause the computing device, while operating as the audio information channel device for the synchrony group, to perform functions comprising:
receive, from at least one of the first zone player or the second zone player via the asynchronous data network, an indication that at least one of the first zone player or the second zone player have successfully joined the synchrony group.

10 . The computing device of claim 1 , wherein transmitting the audio information to the first and second zone players over the asynchronous data network comprises:
transmitting a series of frames, wherein individual frames comprise audio information representing a respective portion of the given 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 individual subsequent frames 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 given audio content in the individual subsequent frame is to be synchronously played back by the first and second zone players.

11 . The computing device of claim 1 , further comprising program instructions stored on the tangible, non-transitory computer-readable medium that, when executed by the at lea

Assignees

• 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