From mboxrd@z Thu Jan 1 00:00:00 1970 From: Marcel Holtmann Subject: Re: Support for the Bluetooth subband codec (SBC) Date: Mon, 08 Nov 2004 13:09:07 +0100 Message-ID: <1099915747.6896.113.camel@pegasus> References: <1099878354.6896.80.camel@pegasus> Mime-Version: 1.0 Content-Type: text/plain Content-Transfer-Encoding: 7bit Return-path: In-Reply-To: Sender: alsa-devel-admin@lists.sourceforge.net Errors-To: alsa-devel-admin@lists.sourceforge.net List-Unsubscribe: , List-Post: List-Help: List-Subscribe: , List-Archive: To: Jaroslav Kysela Cc: alsa-devel@lists.sourceforge.net List-Id: alsa-devel@alsa-project.org Hi Jaroslav, > > besides the Bluetooth headset/handsfree support there is another type of > > audio support. It is the high quality audio (A2DP) for headphones and so > > on. To include a native support for these devices with every Bluetooth > > adapter (for example the ones built into your notebook) it is necessary > > to support the subband codec (SBC) from Philips. The codec description > > is in the Advanced Audio Distribution Profile (A2DP). > > > > I am not an audio expert and far away from doing any codec specific > > things, but from my understanding the ALSA kernel part should be > > extended with the SBC type for PCM devices and the library should know > > how to convert any PCM data into the SBC format so we can use it inside > > the kernel in a A2DP driver. > > Any datasheet for this format? Anyway, if SBC format only encapsulates > linear PCM samples to packets, then it should be handled in the driver > like the USB driver does. the datasheet for this codec can be found on the Bluetooth specification webpage (www.bluetooth.org/spec/). It is part of the A2DP document. I think you need to be logged in to get it and so I will send it to you in a private mail later. I don't think that this is linear PCM, but actually I am no expert when it comes to codec specific stuff. I would be great if you can take a look at it and tell me what you think how we should support it. Regards Marcel ------------------------------------------------------- This SF.Net email is sponsored by: Sybase ASE Linux Express Edition - download now for FREE LinuxWorld Reader's Choice Award Winner for best database on Linux. http://ads.osdn.com/?ad_id=5588&alloc_id=12065&op=click