Synchronizing Playback by Media Playback Devices

Patent metadata

Field	Value
Publication number	US-2022188068-A1
Application number	US-202217686566-A
Country	US
Kind code	A1
Filing date	Mar 4, 2022
Priority date	Jul 28, 2003
Publication date	Jun 16, 2022
Grant date	—

Abstract

Example systems, apparatus, and methods receive audio information including a plurality of frames from a source device, wherein each frame of the plurality of frames includes one or more audio samples and a time stamp indicating when to play the one or more audio samples of the respective frame. In an example, the time stamp is updated for each of the plurality of frames using a time differential value determined between clock information received from the source device and clock information associated with the device. The updated time stamp is stored for each of the plurality of frames, and the audio information is output based on the plurality of frames and associated updated time stamps. A number of samples per frame to be output is adjusted based on a comparison between the updated time stamp for the frame and a predicted time value for play back of the frame.

First claim

What is claimed is:

1 . A first zone player comprising:
a network interface that is configured to communicatively couple the first zone player to at least one data network; a clock that is configured to provide a clock time of the first zone player; at least one processor; and tangible, non-transitory computer-readable media comprising program instructions executable by the at least one processor such that the first zone player is configured to: operate as a standalone zone player that is configured to play back audio individually rather than in synchrony with another zone player; while operating as a standalone zone player, receive a request to enter into a synchrony group with at least a second zone player that is communicatively coupled to the first zone player via the at least one data network, wherein the second zone player comprises its own respective clock that is configured to provide a clock time of the second zone player; after receiving the request to enter into the synchrony group, enter into the synchrony group with the second zone player, wherein, while in the synchrony group, the first zone player is configured to: receive, from the second zone player via the at least one data network, (i) clock information comprising an indication of the clock time of the second zone player, and (ii) a series of frames comprising audio information that is representative of given audio content, playback timing information associated with the audio information that comprises an indicator of at least a first future time at which the first and second zone players are to initiate synchronous playback of the received audio information, and an indication of a sample rate of the audio information, wherein individual frames include corresponding sequence numbers that identify relative positions of the individual frames within the series of frames; order the received frames based on the sequence numbers; decode the received audio information; when a clock rate of the first zone player differs from a clock rate of the second zone player, adjust the sample rate of at least a portion of the audio information to compensate for the difference between the clock rate of the first zone player and the clock rate of the second zone player; and play back the received audio information in synchrony with the second zone player based at least in part on (i) the clock time of the first zone player, (ii) the received playback timing information, and (iii) the sample rate of the audio information.

2 . The first zone player of claim 1 , wherein the program instructions executable by the at least one processor such that the first zone player is configured to receive the request to enter into the synchrony group with at least the second zone player comprise program instructions executable by the at least one processor such that the first zone player is configured to:
receive the request to enter into the synchrony group with at least the second zone player from one or both of (a) a network device that is communicatively coupled to the first zone player via the at least one data network or (b) the second zone player.

3 . The first zone player of claim 1 , wherein the first future time comprises a future time relative to the clock time of the second zone player.

4 . The first zone player of claim 1 , wherein the program instructions executable by the at least one processor such that the first zone player is configured to play back the received audio information in synchrony with the second zone player based at least on (i) the clock time of the first zone player, (ii) the received playback timing information, and (iii) the sample rate of the audio information comprise program instructions executable by the at least one processor such that the first zone player is configured to:
determine whether the clock rate of the first zone player differs from the clock rate of the second zone player based on the clock time of the first zone player and the received clock information comprising the indication of the clock time of the second zone player.

5 . The first zone player of claim 1 , wherein the program instructions executable by the at least one processor such that the first zone player is configured to adjust the sample rate of at least a portion of the audio information to compensate for the difference between the clock rate of the first zone player and the clock rate of the second zone player comprise program instructions executable by the at least one processor such that the first zone player is configured to:
based on one or both of the received clock information or the received playback timing information, either increase or decrease an amount of at least the portion of the audio information that is representative of the given audio content to compensate for the difference between the clock rate of the first zone player and the clock rate of the second zone player.

6 . The first zone player of claim 1 , wherein the program instructions executable by the at least one processor such that the first zone player is configured to adjust the sample rate of at least a portion of the audio information to compensate for the difference between the clock rate of the first zone player and the clock rate of the second zone player comprise program instructions executable by the at least one processor such that the first zone player is configured to:
based on one or both of the received clock information or the received playback timing information, determine whether the clock rate of the first zone player is greater than the clock rate of the second zone player; and when the clock rate of the first zone player is greater than the clock rate of the second zone player, increase an amount of at least the portion of the received audio information that is representative of the given audio content.

7 . The first zone player of claim 1 , wherein the program instructions executable by the at least one processor such that the first zone player is configured to adjust the sample rate of at least a portion of the audio information to compensate for the difference between the clock rate of the first zone player and the clock rate of the second zone player comprise program instructions executable by the at least one processor such that the first zone player is configured to:
based on one or both of the received clock information or the received playback timing information, determine whether the clock rate of the first zone player is less than the clock rate of the second zone player; and when the clock rate of the first zone player is less than the clock rate of the second zone player, decrease an amount of at least the portion of the audio information that is representative of the given audio content.

8 . The first zone player of claim 1 , wherein, in the synchrony group, the first zone player is further configured to:
transmit, to the second zone player via the at least one data network, clock information comprising an indication of the clock time of the first zone player, wherein the clock information comprising the indication of the clock time of the first zone player is used by the second zone player to facilitate the synchronous playback of the audio information by the second zone player with the first zone player.

9 . Tangible, non-transitory computer-readable media comprising instructions stored therein, wherein the instructions, when executed, cause a first zone player to perform functions comprising:
operating as a standalone zone player that is configured to play back audio individually rather than in synchrony with another zone player; while operating as a standalone zone player, receiving a request to enter into a synchrony group with at least a secon

Assignees

• Sonos Inc

Inventors

• Millington Nicholas A J
• Ericson Michael Darrell Andrew

Classifications

• H04R2227/005

  Audio distribution systems for home, i.e. multi-room use · 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

• G06F3/0484

  for the control of specific functions or operations, e.g. selecting or manipulating an object, an image or a displayed text element, setting a parameter value or selecting a range · CPC title

• H04R2227/003

  Digital PA systems using, e.g. LAN or internet · CPC title

• G06F17/00

  Digital computing or data processing equipment or methods, specially adapted for specific functions (information retrieval, database structures or file system structures therefor G06F16/00) · CPC title