View Full Version : A2dp


Jaybird180
03-26-2008, 03:29 PM
Where can I find info about integrating this capability into the car?

What is A2DP?
Advanced Audio Distribution Profile (A2DP)
This profile defines how high quality audio (stereo (http://en.wikipedia.org/wiki/Stereo) or mono (http://en.wikipedia.org/wiki/Mono)) can be streamed from one device to another over a Bluetooth (http://en.wikipedia.org/wiki/Bluetooth) connection.[1] (http://en.wikipedia.org/wiki/A2DP#cite_note-0) For example, music streamed from a mobile phone (http://en.wikipedia.org/wiki/Mobile_phone) to a wireless headset (http://en.wikipedia.org/wiki/Headphones).
A2DP was initially used in conjunction with an intermediate Bluetooth transceiver that connects to a standard output audio jack, encodes the incoming audio to a Bluetooth-friendly format, and sends the signal wirelessly to Bluetooth headphones that decode and play the audio. However, many Bluetooth 1.1, 1.2 mobile phones (http://en.wikipedia.org/wiki/Mobile_phones) and portable media players (http://en.wikipedia.org/wiki/Portable_media_player) do not natively support A2DP, while some newer Bluetooth 2.0 headphones do support it.
Bluetooth headphones, especially the more advanced models, often come with a microphone and support for the Headset (HSP) (http://en.wikipedia.org/wiki/A2DP#Headset_Profile_.28HSP.29), Hands-Free (HFP) (http://en.wikipedia.org/wiki/A2DP#Hands-Free_Profile_.28HFP.29) and Audio/Video Remote Control (AVRCP) (http://en.wikipedia.org/wiki/A2DP#Audio.2FVideo_Remote_Control_Profile_.28AVRCP .29) profiles.
A2DP is designed to transfer a 2-channel stereo audio stream, like music from an MP3 player (http://en.wikipedia.org/wiki/Digital_audio_player), to a headset or car radio.[2] (http://en.wikipedia.org/wiki/A2DP#cite_note-1) This profile relies on AVDTP (http://en.wikipedia.org/w/index.php?title=AVDTP&action=edit&redlink=1) and GAVDP (http://en.wikipedia.org/w/index.php?title=GAVDP&action=edit&redlink=1). It includes mandatory support for the low complexity SBC codec and supports optionally: MPEG-1 (http://en.wikipedia.org/wiki/MPEG-1), MPEG-2 (http://en.wikipedia.org/wiki/MPEG-2), MPEG-4 (http://en.wikipedia.org/wiki/MPEG-4), AAC (http://en.wikipedia.org/wiki/Advanced_Audio_Coding), and ATRAC (http://en.wikipedia.org/wiki/ATRAC), and is extensible to support manufacturer-defined codecs (http://en.wikipedia.org/wiki/Codec). Most bluetooth stacks implement the SCMS-T (http://en.wikipedia.org/wiki/Serial_Copy_Management_System) digital rights management (http://en.wikipedia.org/wiki/Digital_rights_management) (DRM) scheme. In these cases it is not possible to connect the A2DP headphones for high quality audio.
(from Wikipedia)