From mboxrd@z Thu Jan 1 00:00:00 1970 From: Rimas Kudelis Subject: Re: Re: [PATCH] Add support for Acer TravelMate and Date: Wed, 01 Mar 2006 09:32:25 +0200 Message-ID: <44054E09.7070901@akl.lt> References: <200602282345.k1SNjPfu020504@auster.physics.adelaide.edu.au> Mime-Version: 1.0 Content-Type: text/plain; charset=ISO-8859-1 Content-Transfer-Encoding: 7bit Return-path: In-Reply-To: <200602282345.k1SNjPfu020504@auster.physics.adelaide.edu.au> 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: Jonathan Woithe Cc: Lee Revell , alsa-devel@lists.sourceforge.net, Paulo Matias List-Id: alsa-devel@alsa-project.org Jonathan Woithe wrote: >>> The "CD" input on the ALC260 is an analog input. It expects the CD drive to >>> do all the audio decoding and present an ordinary stereo signal to this pin. >>> If when playing a CD and enabling the "CD" control you get no audio that >>> strongly suggests that there is no audio signal running to that pin. >>> However, if there is no analog connection to the ALC260 one does wonder >>> precisely how these systems are expected to play CDs. The only option >>> left would be for software to read the raw CD bitstream (which isn't a straight >>> audio bitstream), decode it and then send the resulting audio bitstream to >>> the DAC. Given that CD drives are more than capable of doing all this it would >>> surprise me if this were the case. >>> >>> One thing worth checking though - have you tested *all* ALC260 inputs with >>> the CD playing? Maybe Acer connect the CD audio to some other ALC260 pin. >>> To be honest, I haven't. I thought the CD pin is a bit different from the others, so I didn't bother to test everything. >> I would not be surprised if some vendors were leaving out the DAC from >> their CD drives, and expect you to play audio CDs in digital mode. I >> believe this is how Windows Media Player works by default (it also >> allows it to generate visual effects from the CD audio). >> > Ah, right. I wasn't aware of that. If that's its default behaviour then > perhaps the Acers do expect the OS to use digital mode for playing CDs. If > this proves to be the case then we'll revise the "acer" model to omit the CD > controls. I believe the Gnome CD player and Sound Juicer applications do that too. I think they, just like all other Gnome apps, use the Gstreamer framework. And I can even see a reason for that - most soundcards only have one set of pins for a CD (i.e. only one cd channel) meanwhile many new desktops come with two CD drives. Add to this what Lee has mentioned, and you get quite a set of reasons to use software to extract audio. Rimas ------------------------------------------------------- This SF.Net email is sponsored by xPML, a groundbreaking scripting language that extends applications into web and mobile media. Attend the live webcast and join the prime developer group breaking into this new coding territory! http://sel.as-us.falkag.net/sel?cmd=lnk&kid=110944&bid=241720&dat=121642