Multi Codec Implementation Guideline for Bluetooth AV Profile
The number of devices that play music using Bluetooth wireless technology has been increasing recently. This is especially true for audio players, mobile phones, and wireless headphones. Bluetooth wireless technology is designed for mobile devices such as mobile phones. However with regard to the music playing function, SBC is the mandatory codec in A2DP. All other formats are optional. Therefore, most of the current portable audio players with Bluetooth wireless technology must convert from the original music data storage format (MP3, AAC, ATRAC,etc) to SBC before transferring the music. But this method needs additional power consumption for SBC encoder/decoder rather than streaming with original codec.