Content playback system, playback device, playback control method and program

• US 8,316,154 B2
• Filed: 12/18/2007
• Issued: 11/20/2012
• Est. Priority Date: 12/25/2006
• Status: Active Grant

• Current Assignee: Sony Corporation (Sony Group Corp.)
• Original Assignee: Sony Corporation (Sony Group Corp.)
• Inventors: Yoneda, Michiaki
• Primary Examiner(s): Lazaro, David
• Assistant Examiner(s): HUQ, FARZANA B
• Application Number:
  US12/002,573
• Publication Number:
  US 20080177822A1
• Time in Patent Office: 1,799 Days
• Field of Search: 709/203, 709217-219, 709/248
• US Class Current: 709/248
• CPC Class Codes: H04L 12/282 based on user interaction within the home receiver circuitry for displaying additional information being controlled by a remote control apparatus H04N21/42204
• CPC Class Codes: H04L 12/2838 Distribution of signals within a home automation network, e.g. involving splitting/multiplexing signals to/from different paths adaptations of television systems for transmission by electric cable for domestic distribution H04N7/106; hybrid transport H04L12/6418; home network arrangements specially adapted for distribution of digital video signals H04N7/24
• CPC Class Codes: H04L 2012/2841 Wireless
• CPC Class Codes: H04L 2012/2849 Audio/video appliances
• CPC Class Codes: H04L 65/1059 End-user terminal functionalities specially adapted for real-time communication
• CPC Class Codes: H04L 65/1093 by adding participants; by removing participants
• CPC Class Codes: H04L 69/28 Timers or timing mechanisms used in protocols
• CPC Class Codes: H04N 21/43076 of the same content streams on multiple devices, e.g. when family members are watching the same movie on different devices
• CPC Class Codes: H04N 21/43615 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 Class Codes: H04N 21/64322 IP

Abstract

A first playback device, upon receiving a synchronized playback command while content playback is in progress, transmits, to a second playback device, information that pertains to the playback content and a synchronized playback start time obtained by adding a predetermined additional time to an elapsed playback time for the content. The second playback device starts receiving content data that begins from the synchronized playback start time from a server. After the data that is memorized in a memory reaches a specified volume, the second playback device transmits a playback preparation completion notification to the first playback device. Once the elapsed playback time for the content reaches the synchronized playback start time, the first playback device transmits a playback start command to the second playback device. Upon receiving this command, the second playback device starts playing back content data that begins from the synchronized playback start time.

Claims

1. A content playback system comprising first and second playback devices that are capable of receiving and playing back content data from a server device and are connected by at least a wired connection or a wireless connection, wherein:

the first playback device comprises;

a first communication portion to communicate data with the server device and the second playback device;

a first memory to store content data received from the server device through the first communication portion;

a first playback portion to play back the content data that is stored in the first memory; and

a first synchronized playback control portion to synchronize playback of the first playback device with the second playback device, wherein synchronizing playback of the first playback device with the second playback device comprises;

in response to receiving a synchronized playback command from a user, transmitting to the second playback device, through the first communication portion, information that pertains to the content data being played back by the first playback portion;

obtaining an elapsed playback time for the content data being played back by the first playback portion at the time of receiving the synchronized playback command;

calculating a synchronized playback start time by adding a predetermined additional time to the elapsed playback time;

transmitting the synchronized playback start time to the second playback device through the first communication portion;

receiving a playback preparation completion notification from the second playback device through the first communication portion; and

in response to an elapsed playback time for the content data being played back by the first playback portion reaching the synchronized playback start time, transmitting a playback start command to the second playback device through the first communication portion, wherein the playback start command is configured to prompt the second playback device to play back the content data as soon as the playback start command is received, at substantially the same timing at which the first playback device plays back the content data, without requiring the second playback device to measure time prior to beginning playback;

and

the second playback device comprises;

a second communication portion to communicate data with the server device and the first playback device;

a second memory to store content data received from the server device through the second communication portion;

a second playback portion to play back the content data that is stored in the second memory; and

a second synchronized playback control portion to synchronize playback of the second playback device with the first playback device, wherein synchronizing playback of the second playback device with the first playback device comprises;

receiving the information and the synchronized playback start time from the first playback device through the second communication portion;

receiving the content data beginning from the synchronized playback start time from the server device and buffering the content data in the second memory;

in response to the content data buffered in the second memory reaching or exceeding a specified amount, transmitting the playback preparation completion notification to the first playback device through the second communication portion; and

as soon as the playback start command is received from the first playback device through the second communication portion, using the second playback portion to start playback of the content data already buffered in the second memory beginning from the synchronized playback start time, at substantially the same timing at which the first playback device plays back the content data, without requiring the second playback device to measure time prior to beginning playback.

2. A first playback device comprising:

a communication portion to communicate data with a server device and at least one other playback device;

a memory to store content data received from the server device through the communication portion;

a playback portion to play back the content data that is stored in the memory; and

a synchronized playback control portion to synchronize playback of the first playback device with a second playback device, wherein synchronizing playback of the first playback device with the second playback device comprises;

in response to receiving a synchronized playback command from a user, transmitting to the second playback device, through the communication portion, information that pertains to the content data being played back by the playback portion;

obtaining an elapsed playback time for the content data being played back by the playback portion at the time of receiving the synchronized playback command;

calculating a synchronized playback start time by adding a predetermined additional time to the elapsed playback time;

transmitting the synchronized playback start time to the second playback device through the communication portion;

receiving, from the second playback device through the communication portion, a playback preparation completion notification indicating that the second playback device has buffered a specified amount of the content data; and

in response to an elapsed playback time for the content data being played back by the playback portion reaching the synchronized playback start time, transmitting a playback start command to the second playback device through the communication portion, wherein the playback start command is configured to prompt the second playback device to play back the buffered content data as soon as the playback start command is received, at substantially the same timing at which the first playback device plays back the content data, without requiring the second playback device to measure time prior to beginning playback.

3. The first playback device according to claim 2, wherein transmitting the information comprises:

in response to receiving the synchronized playback command, transmitting, through the communication portion to at least one other playback device, search information to search for the second playback device to join in synchronized playback; and

in response to receiving, from the second playback device through the communication portion, a joining response that indicates that the second playback device will join in synchronized playback, transmitting the information through the communication portion to the second playback device.

4. The first playback device according to claim 2, wherein synchronizing playback of the first playback device with the second playback device further comprises:

in response to receiving a joining request from a third playback device through the communication portion while the first playback device and the second playback device are playing back content data at substantially the same timing, transmitting to the third playback device, through the communication portion, information that pertains to the content data that is being played back and information that indicates a second synchronized playback start time obtained by adding the predetermined additional time to an elapsed playback time for the content data being played back at the time of receiving the joining request;

receiving a playback preparation completion notification from the third playback device through the communication portion; and

in response to an elapsed playback time for the content data being played back reaching the second synchronized playback start time, transmitting the playback start command to the third playback device through the communication portion.

5. The first playback device according to claim 2, wherein synchronizing playback of the first playback device with the second playback device further comprises:

transmitting to the second playback device, through the communication portion, information that pertains to next content data;

receiving the next content data through the communication portion from the server device and storing the next content data in the memory;

in response to receiving a next playback preparation completion notification from the second playback device through the communication portion, transmitting a second playback start command for the next content data to the second playback device through the communication portion; and

prompting the playback portion to begin playing back the next content data that is stored in the memory.

6. The first playback device according to claim 2, wherein synchronizing playback of the first playback device with the second playback device further comprises:

requesting, while the first playback device and the second playback device are playing back content data at substantially the same timing, an elapsed playback time for the content data from the second playback device;

receiving from the second playback device, through the communication portion, information that indicates the elapsed playback time for the content data being played back by the second playback device;

comparing the elapsed playback time from the second playback device with an elapsed playback time for the content data being played back by the first playback device;

if the elapsed playback time from the second playback device differs from the elapsed playback time at the first playback device by a predetermined time or more, transmitting a playback stop command to the second playback device through the communication portion;

transmitting to the second playback device, through the communication portion, fourth information that indicates a new synchronized playback start time obtained by adding the predetermined additional time to an elapsed playback time for the content data being played back by the first playback device at the time of transmitting the playback stop command;

receiving a second playback preparation completion notification from the second playback device through the communication portion; and

in response to an elapsed playback time for the content data being played back by the first playback device reaching the new synchronized playback start time, transmitting a second playback start command to the second playback device through the communication portion.

7. The first playback device according to claim 2, further comprising:

a mode setting portion that sets, in response to receiving the synchronized playback command, a playback control mode of the first playback device to a master mode in which the first playback device controls content data playback in the second playback device.

8. A first playback device comprising:

a communication portion that communicates data with a server device and at least one other playback device;

a memory that stores content data received from the server device through the communication portion;

a playback portion that plays back the content data that is stored in the memory; and

a synchronized playback control portion that synchronizes playback of the first playback device with a second playback device, wherein synchronizing playback of the first playback device with the second playback device comprises;

receiving, from the second playback device through the communication portion, first information that pertains to content data being played back by the second playback device and second information that indicates a synchronized playback start time representing a predetermined additional time added to an elapsed playback time at the second playback device;

based at least on the first and second information, receiving the content data beginning from the synchronized playback start time from the server device and buffering the content data in the memory;

in response to the content data buffered in the memory reaching or exceeding a specified amount, transmitting a playback preparation completion notification to the second playback device through the communication portion; and

as soon as a playback start command is received from the second playback device, prompting the playback portion to start playback of the content data already buffered in the memory beginning from the synchronized playback start time, at substantially the same timing at which the second playback device plays back the content data, without requiring the first playback device to measure time prior to beginning playback.

9. The first playback device according to claim 8, wherein synchronizing playback of the first playback device with the second playback device further comprises:

receiving search information from the second playback device through the communication portion;

determining whether to allow synchronized playback with the second playback device based at least on setting information that is set in advance; and

if synchronized playback is allowed, transmitting to the second playback device, through the communication portion, a joining response that indicates that the first playback device will join in synchronized playback with the second playback device.

10. The first playback device according to claim 8, wherein synchronizing playback of the first playback device with the second playback device further comprises:

in response to receiving a synchronized playback command while playback by the first playback device is stopped, and while the second playback device and a third playback device are playing back the content data at substantially the same timing, transmitting a joining request to the second and third playback devices through the communication portion.

11. The first playback device according to claim 8, wherein synchronizing playback of the first playback device with the second playback device further comprises:

receiving from the second playback device, through the communication portion, third information that pertains to next content data;

receiving the next content data from the server device through the communication portion and storing the next content data in the memory;

in response to the next content data stored in the memory reaching or exceeding a specified amount, transmitting a next playback preparation completion notification to the second playback device through the communication portion; and

in response to receiving a playback start command from the second playback device, prompting the playback portion to begin playing back the next content data that is stored in the memory.

12. The first playback device according to claim 8, wherein synchronizing playback of the first playback device with the second playback device further comprises:

in response to receiving a request from the second playback device while the first playback device and the second playback device are playing back the content data at substantially the same timing, transmitting to the second playback device, through the communication portion, third information that indicates an elapsed time for the content data being played back by the first playback device;

receiving a playback stop command from the second playback device through the communication portion;

stopping playback of the content data upon receiving the playback stop command;

receiving from the second playback device, through the communication portion, fourth information that indicates a new synchronized playback start time;

receiving the content data beginning from the new synchronized playback start time from the server device through the communication portion and storing the content data in the memory;

in response to the content data stored in the memory reaching or exceeding a specified amount, transmitting a second playback preparation completion notification to the second playback device through the communication portion; and

in response to receiving a second playback start command from the second playback device through the communication portion, prompting the playback portion to begin playing back the content data stored in the memory beginning from the new synchronized playback start time.

13. The first playback device according to claim 9, further comprising:

a mode setting portion that sets, when synchronized playback is allowed, a playback control mode of the first playback device to a slave mode in which content data playback is controlled by the second playback device.

14. A playback control method for a first playback device that plays back content data received from a server device in synchronization with at least one other playback device, the method comprising:

playing back content data received from the server device;

in response to receiving a synchronized playback command from a user while playing back the content data, transmitting to a second playback device information that pertains to the content data being played back;

obtaining an elapsed playback time for the content data being played back at the time of receiving the synchronized play back command;

calculating a synchronized playback start time by adding a predetermined additional time to the elapsed playback time;

transmitting the synchronized playback start time to the second playback device;

receiving, from the second playback device, a playback preparation completion notification indicating that the second playback device has buffered a specified amount of the content data; and

in response to an elapsed playback time for the content data being played back reaching the synchronized playback start time, transmitting a playback start command to the second playback device, wherein the playback start command is configured to prompt the second playback device to play back the buffered content data as soon as the playback start command is received, at substantially the same timing at which the first playback device plays back the content data, without requiring the second playback device to measure time prior to beginning playback.

15. The playback control method according to claim 14, wherein transmitting the information comprises:

in response to receiving the synchronized playback command, transmitting to at least one other playback device search information searching for the second playback device to join in synchronized playback; and

in response to receiving, from the second playback device, a joining response that indicates that the second playback device will join in synchronized playback, transmitting the information to the second playback device.

16. The playback control method according to claim 14, further comprising:

in response to receiving a joining request from a third playback device while the first playback device and the second playback device are playing back content data at substantially the same timing, transmitting to the third playback device information that pertains to the content data that is being played back and information that indicates a second synchronized playback start time obtained by adding the predetermined additional time to an elapsed playback time for the content data being played back at the time of receiving the joining request;

receiving a playback preparation completion notification from the third playback device; and

in response to an elapsed playback time for the content data being played back reaching the second synchronized playback start time, transmitting the playback start command to the third playback device.

17. The playback control method according to claim 14, further comprising:

transmitting to the second playback device information that pertains to next content data;

receiving the next content data from the server device and storing the next content data in a memory;

in response to receiving a next playback preparation completion notification from the second playback device, transmitting the playback start command for the next content data to the second playback device; and

starting playback of the next content data that is stored in the memory.

18. The playback control method according to claim 14, further comprising:

requesting, while the first playback device and the second playback device are playing back content data at substantially the same timing, an elapsed playback time for the content data from the second playback device;

receiving from the second playback device information that indicates the elapsed playback time for the content data being played back by the second playback device;

comparing the elapsed playback time from the second playback device with an elapsed playback time for the content data being played back by the first playback device;

if the elapsed playback time from the second playback device differs from the elapsed playback time at the first playback device by a predetermined time or more, transmitting a playback stop command to the second playback device;

transmitting to the second playback device information that indicates a second synchronized playback start time obtained by adding the predetermined additional time to an elapsed playback time for the content data being played back by the first playback device at the time of transmitting the playback stop command;

receiving a second playback preparation completion notification from the second playback device; and

in response to an elapsed time for the content data being played back by the first playback device reaching the second synchronized playback start time, transmitting a second playback start command to the second playback device.

19. The playback control method according to claim 14, further comprising:

setting, in response to receiving the synchronized playback command, a playback control mode of the first playback device to a master mode in which the first playback device controls content data playback in the second playback device.

20. A playback control method for a first playback device that plays back content data received from a server device in synchronization with at least one other playback device, the method comprising:

receiving, from a second playback device, first information that pertains to content data being played back by the second playback device and second information that indicates a synchronized playback start time representing a predetermined additional time added to an elapsed playback time at the second playback device;

based at least on the first and second information, receiving the content data beginning from the synchronized playback start time from the server device and buffering the content data in a memory;

in response to the content data buffered in the memory reaching or exceeding a specified amount, transmitting to the second playback device a playback preparation completion notification; and

as soon as a playback start command is received from the second playback device, starting playback of the content data already buffered in the memory beginning from the synchronized playback start time, at substantially the same timing at which the second playback device plays back the content data, without requiring the first playback device to measure time prior to beginning playback.

21. The playback control method according to claim 20, further comprising:

receiving search information from the second playback device;

determining whether to allow synchronized playback with the second playback device based at least on setting information that is set in advance; and

if synchronized playback is allowed, transmitting to the second playback device a joining response that indicates that the first playback device will join in synchronized playback with the second playback device.

22. The playback control method according to claim 20, further comprising:

in response to receiving a synchronized playback command while playback by the first playback device is stopped, and while the second playback device and a third playback device are playing back content data at substantially the same timing, transmitting a joining request to the second and third playback devices.

23. The playback control method according to claim 20, further comprising:

receiving, from the second playback device, third information that pertains to next content data;

receiving the next content data from the server device and storing the next content data in the memory;

in response to the next content data stored in the memory reaching or exceeding a specified amount, transmitting to the second playback device a next playback preparation completion notification; and

in response to receiving a next playback start command from the second playback device, starting playback of the next content data that is stored in the memory.

24. The playback control method according to claim 20, further comprising:

in response to receiving a request from the second playback device while the first playback device and the second playback device are playing back content data at substantially the same timing, transmitting to the second device third information that indicates an elapsed playback time for the content data being played back by the first playback device;

receiving a playback stop command from the second playback device;

stopping playback of the content data in response to receiving the playback stop command;

receiving, from the second playback device, fourth information that indicates a new synchronized playback start time;

receiving the content data beginning from the new synchronized playback start time from the server device and storing the content data in the memory;

in response to the content data stored in the memory reaching or exceeding a specified amount, transmitting a second playback preparation completion notification to the second playback device; and

in response to receiving a second playback start command from the second playback device, starting playback of the content data stored in the memory beginning from the new synchronized playback start time.

25. The playback control method according to claim 21, further comprising:

setting, when synchronized playback is allowed, a playback control mode of the first playback device to a slave mode in which content data playback is controlled by the second playback device.