Enabling implementation of audio applications using Bluetooth technology
Tokyo, July 7, 2006 −− Renesas Technology Corp. today announced "SBC Middleware" software supporting the SBC (Subband Codec) audio data coding method stipulated in Bluetooth*1 technology for short-range wireless communications, for microprocessors incorporating Renesas Technology’s 32-bit RISC processor SuperH™*2 Family SH3-DSP CPU core. This new middleware will be available from July 20, 2006 in Japan.
SBC is a coding method stipulated in the A2DP (Advanced Audio Distribution Profile) audio data profile defined by the Bluetooth technology specifications. The SH3-DSP CPU core is suitable for mobile device use, and can implement audio-related applications for Bluetooth devices, in mobile audio devices including mobile phones and the like.
Features of this new middleware are summarized below.
|(1) ||Provides development solutions for audio applications in Bluetooth devices |
| ||This middleware comprises "SBC Encode Middleware" that encodes audio data on the transmitting side, and "SBC Decode Middleware" that decodes audio data on the receiving side. Thus, the development of both transmitting-side and receiving-side devices can be supported, enabling development solutions to be provided for audio applications in Bluetooth devices. |
|(2) ||Low processing load achieved through optimization for the SH3-DSP CPU core |
| ||The SBC Middleware algorithm is optimized for the architecture of the SH3-DSP. This enables low-power operation of A2DP compliant audio applications, with a low CPU processing load at the 30-plus MHz level, providing an ample margin for supporting mobile audio devices that require low power consumption. |
|(3) ||C-language interface for more efficient user application development |
| ||As a program interface, a variety of function interfaces are available using easily-embedded C-language. The user only has to write a desired function interface within a program, making complex programming unnecessary, and thus enabling application development to be made more efficient. In addition, Renesas Technology's existing MP3 and MPEG-4 AAC (Advanced Audio Coding) audio middleware uses the same kind of interfacing as this new middleware, simplifying the development of multi-codec applications. |
< Product Background >
Bluetooth technology is a short-range wireless communication method. In recent years, an increasing number of systems providing wireless transfer and playback of data by means of Bluetooth technology have appeared in such products as mobile audio devices and in-vehicle audio systems. An essential requirement for implementing a Bluetooth audio application is compliance with the SBC audio data coding method stipulated in the Bluetooth A2DP audio profile.
Renesas Technology has released various semiconductor devices for use in multimedia products, and also offers a lineup of moving image middleware for MPEG-4 and similar applications and audio middleware for MP3 and MPEG-4 AAC applications and the like.
Now, to provide enhanced multimedia application development solutions, Renesas Technology has developed SBC Middleware for the SH3-DSP CPU core, for use in the development of audio applications in Bluetooth devices, which are expected to become increasingly popular in the future.
< Additional Product Details >
SBC is a highly efficient coding method specified by Bluetooth Special Interest Group (SIG) as a standard audio codec in a Bluetooth device. In the A2DP audio data profile of Bluetooth technology, SBC is essential as an audio data coding method for maintaining interconnectivity, and MP3 and MPEG-4 AAC are specified as options.
SBC Middleware is compliant with the A2DP specification, and comprises "SBC Encode Middleware" and "SBC Decode Middleware." In audio data transmission, SBC Encode Middleware encodes 16-bit linear PCM (Pulse Code Modulation) data and generates an SBC bit stream. SBC Decode Middleware is used in audio data reception, decoding a received SBC bit stream and generating 16-bit linear PCM data. In this way, the development of both transmitting-side and receiving-side devices can be supported.
The SBC Middleware algorithm is optimized for the architecture of the SH3-DSP CPU core. Encoding and decoding are implemented at low CPU processing load levels of 36 MHz (typ.) and 37 MHz (typ.) respectively, contributing to the creation of low-power devices.
This middleware offers C-language function interfaces. This means that the user only has to write the relevant function interface within a program, simplifying the development of an A2DP compatible application. This interfacing is equivalent to the MP3 and MPEG-4 AAC middleware interfacing previously offered by Renesas Technology, facilitating multi-codec implementation for audio codec in Bluetooth devices.
Future plans include the development of this middleware for use with microprocessors incorporating an SH-4 CPU core, and expansion into other application areas such as in-vehicle audio systems.
|Notes: ||1. ||The Bluetooth® word mark and logo are registered trademarks and are owned by the Bluetooth SIG, Inc., and any use of such marks by Renesas Technology is under license. |
Bluetooth SIG, Inc. Web site: http://www.bluetooth.com/
|2. ||SuperH is a trademark of Renesas Technology Corp. |
* Other product names, company names, or brands mentioned are the property of their respective owners.
Development of audio applications for Bluetooth devices using a SuperH Family microprocessor incorporating an SH3-DSP CPU core
|Item ||Specifications |
|Applicable devices ||SuperH Family microprocessors incorporating SH3-DSP CPU core |
|Standard compliance ||Bluetooth SIG, Inc. |
Advanced Audio Distribution Profile Specification v1.0
|Functions ||SBC compliant digital audio expansion/compression functions |
|Sampling rate ||16/32/44.1/48 KHz |
|Bit rate ||96 kbps to 512 Kbps |
|Processing load ||SBC Decoding Middleware: 37 MHz (typ.) |
SBC Encoding Middleware: 36 MHz (typ.)
- Bluetooth SIG compliant test data used
- Joint-stereo, 48 KHz, 512 Kbps, Loudness mode