Time to play

Patent metadata

Field	Value
Publication number	US-9788140-B2
Application number	US-201414587792-A
Country	US
Kind code	B2
Filing date	Dec 31, 2014
Priority date	Dec 31, 2014
Publication date	Oct 10, 2017
Grant date	Oct 10, 2017

Abstract

A device capable of operating according to a wireless communications protocol, the device being configured to: receive media data from one of a plurality of inputs; determine an offset period of time in dependence on which one of the plurality of inputs the media data is received from; determine a time for playing the received media data in dependence on the determined offset period and a clock value; encapsulate the media data and time data representing the determined time in a broadcast packet; and broadcast the packet in accordance with the wireless communications protocol.

First claim

The invention claimed is:

1. A device capable of operating according to a wireless communications protocol, the device being configured to:
receive media data from one of a plurality of inputs;
determine an offset period of time based on which input of the plurality of inputs the media data is received from, wherein the offset period of time is determined based on a predetermined period of time having a duration that compensates for reception delays between bursts of media data associated with the input;
determine a time for playing the received media data based on the determined offset period and a clock value;
encapsulate the media data and time data representing the determined time for playing in a broadcast packet; and
broadcast the broadcast packet in accordance with the wireless communications protocol to one or more remote devices configured to play out the media data at the determined time for playing.

2. The device of claim 1 , wherein the plurality of inputs comprise a first input and a second input, wherein the determined offset period is a first time period if the media data is received from the first input and the determine offset period is a second time period if the media data is received from the second input, the first time period being different to the second time period.

3. The device of claim 2 , wherein the first input is burstier than the second input and the first time period is greater than the second time period.

4. The device of claim 1 , wherein the time for playing is determined based on a sample rate at which media data is received.

5. The device of claim 1 , wherein the offset period of time is determined based on a first estimated period of time for processing the media data for playback and a second estimated period of time for processing the media data for broadcasting.

6. The device of claim 5 , wherein the offset period of time is determined further based on a third estimated period of time for receiving the broadcasted packet at another device and a fourth estimated period of time for processing the received packet for playing back the media data.

7. The device of claim 1 , wherein a sequence number for the media data is represented by the time data.

8. The device of claim 1 , wherein the received media is encoded according to a first codec, the device being further configured to:
decode the received media data;
temporarily store the decoded media data and the time data in a buffer;
encode the stored media data according to a second codec different to the first codec, wherein the encapsulated media data is the encoded media data; and
play the stored decoded media data at the determined time for playing.

9. The device of claim 1 , wherein the device comprises a playback device configured to play the media data at the time indicated by the time data.

10. The device of claim 1 , wherein the broadcast is unidirectional.

11. The device of claim 1 , wherein the wireless communications protocol mandates that the one or more remote devices receiving broadcasted packets do not send acknowledgement messages to confirm receipt of the broadcasted packets.

12. The device of claim 1 , wherein the wireless communications protocol is Bluetooth.

13. The device of claim 12 , wherein the broadcast is a connectionless slave broadcast.

14. The device of claim 12 , wherein the media data is received via an A2DP link of the Bluetooth communications protocol.

15. The device of claim 1 , wherein device is further configured to encapsulate control data in the broadcast packet, wherein the control data is configured to cause the one or more remote devices to perform a control function at a time indicated by the time data.

16. A device capable of operating according to a wireless communications protocol, the device being configured to:
receive a broadcast packet broadcasted in accordance with the wireless communications protocol from a hub device, wherein the broadcast packet comprises media data and time data, the time data representing a time for playing the media data at the device that is based on an offset period of time, and wherein the offset period of time is based on a predetermined period of time having a duration that compensates for reception delays between bursts of media data associated with an input from which the media data is received at the hub device;
decode the media data;
determine the time for playing the decoded media data based on the time data and a clock; and
play the decoded media data at the determined time for playing.

17. The device of claim 16 , wherein the broadcast packet is received from the hub device using a link defined by the wireless communication protocol, the device being configured to not transmit packets to the hub device using the link.

18. A method of broadcasting a stream of packets comprising:
receiving a stream of media frames from one of a plurality of inputs;
determining an offset period of time based on which one of the plurality of inputs the media frames are received from, wherein the offset period of time is determined based on a predetermined period of time having a duration that compensates for reception delays between bursts of media data associated with the input;
determining a time for playing each of the received media frames based on the determined offset period and a clock;
broadcasting a stream of packets comprising the media frames and the determined time for playing for each media frame in accordance with a wireless communications protocol to one or more remote devices configured to play out each media frame at the determined time for playing the media frame.

19. The method of claim 18 , wherein the wireless communications protocol is a Bluetooth protocol and the stream is broadcast in the connectionless slave broadcast mode of the Bluetooth protocol.

20. A communications device capable of operating according to a wireless communications protocol, the device being configured to:
receive media from an input;
estimate a period of time for the media to be received by one or more remote devices from the communication device, wherein the period of time is estimated based on a predetermined period of time having a duration that compensates for reception delays between bursts of media data associated with the input;
determine a play out time for playing out the media based on the estimated period and a clock value;
encapsulate the media and the play out time in a broadcast packet; and
broadcast the broadcast packet in accordance with the wireless communications protocol to the one or more remote devices configured to play out the media at the determined play out time.

21. The communications device of claim 20 , wherein the period of time is estimated based on an amount of time for a packet to be transported from the communications device to the one or more remote devices.

22. The communications device of claim 20 , wherein the period of time is estimated based on a number of times a packet is relayed for transporting that packet from the communications device to the one or more remote devices.

23. The communications device of claim 20 , wherein the period of time is estimated based on whether or not the one or more remote devices is within direct communications range of the communications device.

24. The communications device of claim 20 , wherein the period of time is estimated on the quality of the media.

25. The communications d

Assignees

• Qualcomm Technologies Int Ltd

Inventors

• Sole Jonathon
• Campbell Benjamin
• Haboubi Harith

Classifications

• H04W72/30

  Resource management for broadcast services · CPC title

• H04N21/4305

  Synchronising client clock from received content stream, e.g. locking decoder clock with encoder clock, extraction of the PCR packets (arrangements for synchronising receiver with transmitter by comparing receiver clock with transmitter clock H04L7/0012; arrangements for synchronising receiver with transmitter wherein the receiver takes measures against momentary loss of synchronisation H04L7/0083) · CPC title

• H04L65/60

  Network streaming of media packets · CPC title

• H04W76/023

  Electricity · mapped topic

• H04W72/005

  Electricity · mapped topic