Controller integrated audio codec for advanced audio distribution profile audio streaming applications

• US 20080287063A1
• Filed: 05/12/2008
• Published: 11/20/2008
• Est. Priority Date: 05/16/2007
• Status: Active Grant

• Current Assignee: Texas Instruments, Inc.
• Original Assignee: Texas Instruments, Inc.
• Inventors: Katz, Ran, Irony, Ran, Dekel, Eli, Kidron, Amihai
• Granted Patent: US 8,224,247 B2
• Time in Patent Office: Days
• US Class Current: 455/41.2
• CPC Class Codes: G10L 19/167 Audio streaming, i.e. formatting and decoding of an encoded audio signal representation into a data stream for transmission or storage purposes
• CPC Class Codes: H04M 1/6025 implemented as integrated speech networks
• CPC Class Codes: H04M 1/6066 including a wireless connection
• CPC Class Codes: H04M 2250/02 including a Bluetooth interface

Abstract

A novel and useful apparatus for and method of integrating the advanced audio distribution profile (A2DP) audio codec into a Bluetooth controller for audio streaming applications. The mechanism functions to break the prior art Bluetooth protocol stack by integrating a profile packet composer into the controller. The profile/stack control signaling is performed by the host while the profile data packet composer is implemented in the controller. The integrated data packet composer does not break the data path and flow control over the standard HCI. Further, the integrated packet composer allows the controller to open a dedicated data interface for specific applications (e.g., PCM/I2S for audio data).

Claims

1. A method of encoding streaming audio in a controller coupled to a communications channel, said method comprising the steps of:

receiving audio streaming data from a host system;

encoding said audio streaming data to generate encoded audio data therefrom; and

assembling transmit packets incorporating said encoded audio data for transmission over said communications channel.

2. The method according to claim 1, wherein said controller comprises a Bluetooth controller and said communications channel comprises a Bluetooth wireless link.

3. The method according to claim 1, wherein said audio streaming data comprises pulse code modulated (PCM) data.

4. The method according to claim 1, wherein said step of encoding comprises encoding pulse code modulated (PCM) input data to subband codec (SBC) format.

5. The method according to claim 1, wherein data path processing is performed by said controller while control functions and associated signaling channel are performed by said host system.

6. The method according to claim 1, wherein said transmit packets comprise Audio/Video Distribution Transport Protocol (AVDTP) packets.

7. A method of encoding streaming audio in a Bluetooth controller, said method comprising the steps of:

receiving pulse code modulated (PCM) format audio streaming data from a host system utilizing a host control application programming interface (API);

encoding said PCM audio streaming data to subband codec (SBC) format; and

generating transmit packets incorporating said SBC encoded audio data for transmission over a Bluetooth link.

8. The method according to claim 7, wherein data path processing is performed by said Bluetooth controller while control functions and associated signaling channel are performed by said host system.

9. The method according to claim 7, wherein said transmit packets comprise Audio % Video Distribution Transport Protocol (AVDTP) packets.

10. The method according to claim 7, wherein said host control API enables said host system to control and configure said Bluetooth controller.

11. The method according to claim 7, wherein said host control API comprises an open stream command operative to establish an advanced audio distribution profile (A2DP) transport channel in said Bluetooth controller.

12. The method according to claim 7, wherein said host control API comprises a close stream command operative to close an advanced audio distribution profile (A2DP) transport channel in said Bluetooth controller.

13. The method according to claim 7, wherein said host control API comprises a codec configuration command operative to configure an SBC codec within said Bluetooth controller.

14. The method according to claim 7, wherein said host control API comprises a multiple sink configuration command operative to configure a plurality of advanced audio distribution profile (A2DP) transport channels in said Bluetooth controller.

15. The method according to claim 7, wherein said host control API comprises a start stream command operative to start SBC data streaming to a remote Bluetooth device.

16. The method according to claim 7, wherein said host control API comprises a stop stream command operative to stop SBC streaming to a remote Bluetooth device.

17. A Bluetooth subband codec (SBC) encoder, comprising:

a host interface operative to receive a pulse code modulated (PCM) format input audio data stream from a host system;

a SBC codec operative to encode said PCM audio data stream into SBC format; and

a profile data packet composer operative to encapsulate said SBC formatted audio data stream to generate Bluetooth transmit packets therefrom.

18. The encoder according to claim 17, wherein said SBC encoder is integrated in a Bluetooth controller whereby data path processing is performed by said controller while control functions and associated signaling channel are performed by said host system.

19. The encoder according to claim 17, wherein said PCM input audio data stream is received from said host system utilizing a host control application programming interface (API).

20. The encoder according to claim 19, wherein said host control API comprises an open stream command, close stream command, codec configuration command, start stream command and a stop stream command.

21. The encoder according to claim 19, wherein said Bluetooth transmit packets comprise Audio/Video Distribution Transport Protocol (AVDTP) packets.

22. A single chip Bluetooth controller, comprising:

a Bluetooth radio for establishing a link to a remote device;

a host interface operative to receive a pulse code modulated (PCM) format input audio data stream from a host system;

an audio encoder operative to encode said audio data stream into subband codec (SBC) format; and

a profile data packet composer operative to encapsulate said SBC formatted audio data stream to generate Bluetooth packets therefrom for transmission by said Bluetooth radio over said link to said remote device.

23. The controller according to claim 22, wherein data path processing is performed by said Bluetooth controller while control functions and associated signaling channel are performed by said host system.

24. The controller according to claim 22, wherein said transmit packets comprise Audio/Video Distribution Transport Protocol (AVDTP) packets.

25. A software program product embodied in a computer-readable medium, comprising program instructions executable to implement:

a host interface for receiving pulse code modulated (PCM) format audio streaming data from a host system utilizing a host control application programming interface (API);

an encoder operative to encode said PCM audio streaming data to subband codec (SBC) format; and

a profile data packet composer operative to encapsulate said SBC formatted audio data stream to generate transmit packets therefrom for transmission over a communications link to a remote device.

26. A software program product embodied in a computer-readable medium, comprising program instructions executable to implement:

a host control application programming interface (API); and

wherein said API defines a plurality of commands for controlling and configuring a Bluetooth controller comprising an interface for receiving a pulse code modulated (PCM) audio data stream from a host system, an encoder for generating subband coding (SBC) formatted audio data and a profile data packet composer operative to encapsulate said SBC formatted audio data to generate Bluetooth packets therefrom.

27. The software program product according to claim 26, wherein said host control API comprises an open stream command operative to establish an advanced audio distribution profile (A2DP) transport channel in said Bluetooth controller.

28. The software program product according to claim 26, wherein said host control API comprises a close stream command operative to close an advanced audio distribution profile (A2DP) transport channel in said Bluetooth controller.

29. The software program product according to claim 26, wherein said host control API comprises a codec configuration command operative to configure an SBC codec within said Bluetooth controller.

30. The software program product according to claim 26, wherein said host control API comprises a multiple sink configuration command operative to configure a plurality of advanced audio distribution profile (A2DP) transport channels in said Bluetooth controller.

31. The software program product according to claim 26, wherein said host control API comprises a start stream command operative to start SBC data streaming to a remote Bluetooth device.

32. The software program product according to claim 26, wherein said host control API comprises a stop stream command operative to stop SBC streaming to a remote Bluetooth device.

33. A method of communicating between an application layer in a host system and a single chip Bluetooth controller incorporating an audio streaming codec and profile data packet composer, said method comprising the steps of:

opening an advanced audio distribution profile (A2DP) signaling and data channel, wherein data channel processing is performed by said Bluetooth controller while control functions and associated signaling channel are performed by said host system;

opening an A2DP stream between said host system and said Bluetooth controller;

configuring a plurality of subband codec (SBC) format encoder parameters, said SBC encoder integrated within said Bluetooth controller;

starting said A2DP stream; and

receiving pulse code modulated (PCM) audio data, encoding said PCM audio data to SBC formatted audio data and composing Bluetooth transmit packets encapsulating said SBC formatted audio data.

34. The method according to claim 33, further comprising the step of stopping said A2DP stream to said Bluetooth controller.

35. The method according to claim 33, further comprising the step of closing said A2DP stream to said Bluetooth controller.

36. The method according to claim 33, wherein said Bluetooth transmit packets comprise Audio/Video Distribution Transport Protocol (AVDTP) packets.

37. A computer implemented method for processing pulse code modulated (PCM) audio streaming data in a Bluetooth controller, comprising:

receiving PCM audio streaming data from a host system utilizing a host control application programming interface (API), wherein said host control API defines a plurality of commands for controlling and configuring a Bluetooth controller, said controller comprising an integrated interface for receiving said PCM audio data stream from a host system, an integrated encoder for generating subband coding (SBC) formatted audio data and an integrated profile data packet composer operative to encapsulate said SBC formatted audio data to generate Bluetooth packets therefrom;

wherein said API comprises a command for opening an advanced audio distribution profile (A2DP) channel between said host system and a remote Bluetooth device;

wherein said API comprises a command for opening an A2DP stream between said host system and said Bluetooth controller;

wherein said API comprises a command for configuring said Bluetooth controller with one or more related parameters;

wherein said API comprises a command for starting an A2DP stream between said host system and said Bluetooth controller; and

receiving pulse code modulated (PCM) audio data, encoding said PCM audio data to SBC formatted audio data and composing Bluetooth transmit packets encapsulating said SBC formatted audio data.

38. The computer implemented method according to claim 37, wherein said API further comprises a command for stopping said A2DP stream to said Bluetooth controller.

39. The computer implemented method according to claim 37, wherein said API further comprises a command for closing said A2DP channel to said remote Bluetooth device.

40. The computer implemented method according to claim 37, wherein said Bluetooth transmit packets comprise Audio/Video Distribution Transport Protocol (AVDTP) packets.

41. A single chip Bluetooth controller, comprising:

a Bluetooth radio for establishing a link to a remote device;

a host control application programming interface (API) defining a plurality of commands for controlling and configuring said Bluetooth controller;

a host interface operative to receive a pulse code modulated (PCM) format input audio data stream from a host system utilizing said host control API;

an audio encoder operative to encode said audio data stream into subband codec (SBC) format; and

a profile data packet composer operative to encapsulate said SBC formatted audio data stream to generate Bluetooth transmit packets therefrom for transmission by said Bluetooth radio over said link to said remote device.

42. The controller according to claim 41, wherein said host control API comprises an open stream command operative to establish an advanced audio distribution profile (A2DP) transport channel in said Bluetooth controller.

43. The controller according to claim 41, wherein said host control API comprises a close stream command operative to close an advanced audio distribution profile (A2DP) transport channel in said Bluetooth controller.

44. The controller according to claim 41, wherein said host control API comprises a codec configuration command operative to configure an SBC codec within said Bluetooth controller.

45. The controller according to claim 41, wherein said host control API comprises a multiple sink configuration command operative to configure a plurality of advanced audio distribution profile (A2DP) transport channels in said Bluetooth controller.

46. The controller according to claim 41, wherein said host control API comprises a start stream command operative to start SBC data streaming to a remote Bluetooth device.

47. The controller according to claim 41, wherein said host control API comprises a stop stream command operative to stop SBC streaming to a remote Bluetooth device.

48. The controller according to claim 41, wherein said Bluetooth transmit packets comprise Audio/Video Distribution Transport Protocol (AVDTP) packets.

49. A method of decoding streaming audio in a controller coupled to a communications channel, said method comprising the steps of:

parsing receive packets incorporating encoded audio received over said communications channel;

decoding said audio streaming data to generate decoded audio data therefrom; and

sending said decoded audio stream data to a host system.

50. A method of decoding streaming audio in a Bluetooth controller, said method comprising the steps of:

parsing receive packets incorporating subband codec (SBC) encoded audio data received over a Bluetooth link;

decoding said SBC format data to pulse code modulated (PCM) format audio streaming data; and

sending said PCM format audio streaming data to a host system utilizing a host control application programming interface (API).