Systems and methods for synchronizing multiple electronic devices

• US 9,967,847 B2
• Filed: 10/26/2017
• Issued: 05/08/2018
• Est. Priority Date: 04/29/2013
• Status: Active Grant

• Current Assignee: Google Technology Holdings LLC (Alphabet Inc.)
• Original Assignee: Google Technology Holdings LLC (Alphabet Inc.)
• Inventors: Daley, Michael J., Bolinger, Travis, O'Neal, Heath
• Primary Examiner(s): HINDI, NABIL Z
• Application Number:
  US15/794,686
• Publication Number:
  US 20180049144A1
• Time in Patent Office: 194 Days
• Field of Search: 360 64, 455 305, 455 306, 4554121, 455502, 455 511, 370260, 370350, 370392, 370432, 370503, 370516, 370528, 375262, 381 2, 381 79, 381 80, 381 82, 386201, 386211, 386219, 700 94, 704260, 709202, 709204, 709208, 709219, 709231, 713500
• CPC Class Codes: H04H 20/08 among terminal devices
• CPC Class Codes: H04H 20/18 Arrangements for synchronising broadcast or distribution via plural systems
• CPC Class Codes: H04H 20/38 Arrangements for distribution where lower stations, e.g. receivers, interact with the broadcast
• CPC Class Codes: H04H 20/57 for mobile receivers
• CPC Class Codes: H04H 20/61 for local area broadcast, e.g. instore broadcast
• CPC Class Codes: H04H 20/63 to plural spots in a confined site, e.g. MATV [Master Antenna Television]
• CPC Class Codes: H04H 60/80 characterised by transmission among terminal devices
• CPC Class Codes: H04H 60/88 which are wireless networks
• CPC Class Codes: H04N 21/242 Synchronization processes, e.g. processing of PCR [Program Clock References] arrangements for synchronising broadcast or distribution via plural systems in broadcast distribution systems H04H20/18
• CPC Class Codes: H04N 21/43 Processing of content or additional data, e.g. demultiplexing additional data from a digital video stream; Elementary client operations, e.g. monitoring of home network or synchronising decoder's clock; Client middleware real-time communication protocols in data switching networks H04L65/00
• CPC Class Codes: H04W 56/0015 one node acting as a reference for the others
• CPC Class Codes: H04W 56/0065 using measurement of signal travel time

Abstract

Embodiments are provided for syncing multiple electronic devices for collective audio playback. According to certain aspects, a master device connects (218) to a slave device via a wireless connection. The master device calculates (224) a network latency via a series of network latency pings with the slave device and sends (225) the network latency to the slave device. Further, the master devices sends (232) a portion of an audio file as well as a timing instruction including a system time to the slave device. The master device initiates (234) playback of the portion of the audio file and the slave devices initiates (236) playback of the portion of the audio file according to the timing instruction and a calculated system clock offset value.

Claims

1. A method comprising:

joining, by an audio playback device, an audio playback group, wherein the audio playback group includes a master device that provides timing information for playback of audio content by the audio playback group;

receiving, by the audio playback device from the master device, a timing signal;

determining, by the audio playback device based on the timing signal, a difference between a clock of the audio playback device and a clock of the master device;

retrieving from memory, by the audio playback device, the difference between the clock of the audio playback device and the clock of the master device;

receiving by the audio playback device from the master device, a first time corresponding to audio data to be played by the audio playback device as part of the audio playback group;

determining by the audio playback device, a second time based on (i) the first time and (ii) the difference between the clock of the audio playback device and the clock of the master device; and

playing, by the audio playback device, the audio data at the second time according to the clock of the audio playback device.

2. The method of claim 1, wherein the audio playback device saves, in the memory, the difference between the clock of the audio playback device and the clock of the master device.

3. The method of claim 1, wherein receiving the timing signal comprises:

receiving, by the audio playback device from the master device, at least one network latency ping indicating the clock of the master device.

4. The method of claim 1, further comprising:

sending, by the audio playback device to the master device, a receipt timing signal, wherein the master device calculates a latency value based on the receipt timing signal;

receiving, by the audio playback device from the master device, the latency value; and

calculating a system clock offset value based on the latency value and the difference between the clock of the audio playback device and the clock of the master device.

5. The method of claim 4, wherein determining the second time comprises:

determining the second time based on (i) the first time and (ii) the system clock offset value.

6. The method of claim 1, wherein receiving the first time corresponding to the audio data to be played by the audio playback device as part of the audio playback group comprises:

receiving by the audio playback device from the master device, (i) the first time and (ii) the audio data.

7. The method of claim 1, wherein playing the audio data at the second time comprises:

scheduling a playback of the audio data at the second time according to the clock of the audio playback device; and

at the second time, initiating the playback of the audio data by the audio playback device.

8. An audio playback device comprising:

a communication component for connecting the audio playback device to a master device;

a memory;

an audio output component for outputting audio; and

a controller module interfaced with the communication component, the memory, and the audio output component, and configured to;

join an audio playback group including the master device that provides timing information for playback of audio content by the audio playback group,

receive, from the master device via the communication component, a timing signal,

determine, based on the timing signal, a difference between a clock of the audio playback device and a clock of the master device,

retrieve, from the memory, the difference between the clock of the audio playback device and the clock of the master device,

receive, from the master device via the communication component, a first time corresponding to audio data to be played by the audio playback device as part of the audio playback group,

determine a second time based on (i) the first time and (ii) the difference between the clock of the audio playback device and the clock of the master device, and

cause the audio output component to play the audio data at the second time according to the clock of the audio playback device.

9. The audio playback device of claim 8, wherein the controller module is further configured to:

cause the memory to save the difference between the clock of the audio playback device and the clock of the master device.

10. The audio playback device of claim 8, wherein the controller module receives the timing signal as at least one network latency ping indicating the clock of the master device.

11. The audio playback device of claim 8, wherein the controller module is further configured to:

send, to the master device via the communication component, a receipt timing signal, wherein the master device calculates a latency value based on the receipt timing signal,

receive, from the master device via the communication component, the latency value, and

calculate a system clock offset value based on the latency value and the difference between the clock of the audio playback device and the clock of the master device.

12. The audio playback device of claim 11, wherein to determine the second time, the processor is configured to:

determine the second time based on (i) the first time and (ii) the system clock offset value.

13. The audio playback device of claim 8, wherein the controller module receives, from the master device via the communication component, (i) the first time and (ii) the audio data.

14. The audio playback device of claim 8, wherein to cause the audio output component to play the audio data at the second time, the controller module is configured to:

schedule a playback of the audio data at the second time according to the clock of the audio playback device, and

at the second time, cause the audio output component to initiate the playback of the audio data.

15. A method comprising:

joining, by an audio playback device, an audio playback group, wherein the audio playback group includes a master device that provides timing information for playback of audio content by the audio playback group;

retrieving from memory, by the audio playback device, data representing a difference between a clock of the audio playback device and a clock of the master device;

receiving by the audio playback device from the master device, a first time corresponding to audio data to be played by the audio playback device as part of the audio playback group;

determining, by the audio playback device, a second time based on (i) the first time and (ii) the difference between the clock of the audio playback device and the clock of the master device; and

playing, by the audio playback device, the audio data at the second time according to the clock of the audio playback device.

16. The method of claim 15, wherein the audio playback device saves, in the memory, the difference between the clock of the audio playback device and the clock of the master device.

17. The method of claim 15, further comprising:

receiving, by the audio playback device from the master device, a timing signal indicating the clock of the master device.

18. The method of claim 17, further comprising:

determining, by the audio playback device based on the timing signal, the difference between the clock of the audio playback device and the clock of the master device.

19. The method of claim 17, further comprising:

sending, by the audio playback device to the master device, a receipt timing signal, wherein the master device calculates a latency value based on the receipt timing signal;

receiving, by the audio playback device from the master device, the latency value; and

calculating a system clock offset value based on the latency value and the difference between the clock of the audio playback device and the clock of the master device.

20. The method of claim 19, wherein determining the second time comprises:

determining the second time based on (i) the first time and (ii) the system clock offset value.