From mboxrd@z Thu Jan 1 00:00:00 1970 From: Petr Gladkikh Subject: alsa-lib: Volume control emulation plugin Date: Sat, 18 Dec 2004 23:10:50 +0600 Message-ID: <41C4649A.9090608@mail.ru> Mime-Version: 1.0 Content-Type: text/plain; charset=ISO-8859-1; format=flowed Content-Transfer-Encoding: 7bit Return-path: 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: alsa-devel@lists.sourceforge.net List-Id: alsa-devel@alsa-project.org Hello. I have on-board sound card which has been mentioned for example in bug "[ALSA - driver 0000725]: Intel8x0, chip CMI9761A - no volume control, sound mixer broken" AFAIK this sound card indeed has no hardware PCM volume control and its "Master" volume control affects only sound which comes from analog inputs. IMHO following solutions which were offered elsewhere look not very elegant (at leas for me ;) 1. "I suggest that forget the mixer and tune the speaker volume." 2. "To reduce the volume, decrease the output level in the application." (I just unable to rewrite every application I need) 3. "use Intel8x0 driver and an extra sound demon (e.g. KDE's artsd)" 4. "use CMedia's OSS driver (avail. at http://www.cmedia.com.tw/download/e_UDA9738_linux_01.htm)" 5. "curse CMedia for building such a crappy chip; curse them again for not releasing an ALSA driver; curse NVidia for using such a crappy chip (older nforce boards had a better chip on-board..); in the end, buy an extra sound card and be happy :)" It seems then that the right solution is to write an ALSA lib plug-in which 1. Accepts input in some format and puts it out being multiplied by some coefficient 0.0..1.0 2. Provides software emulated volume control which can change the coefficient (so ALSA applications can use it) "route" plug-in is almost there but it allows to set volume in configuration file not dynamically, and I do not know how to emulate volume control in ALSA lib with it. So here is the question: does anyone have written/going to write such plug-in? If so how can I help to make it happen (testing, write some code)? (I do not have experience with ALSA to write it completely by myself). BTW I was unable to read bug track database even for read-only due to denied access. Is there any anonymous access? / Petr Gladkikh ------------------------------------------------------- SF email is sponsored by - The IT Product Guide Read honest & candid reviews on hundreds of IT Products from real users. Discover which products truly live up to the hype. Start reading now. http://productguide.itmanagersjournal.com/