From mboxrd@z Thu Jan 1 00:00:00 1970 From: Takashi Iwai Subject: format extension patchset available (24bit support on USB audio) Date: Wed, 19 Jun 2002 16:56:27 +0200 Sender: alsa-devel-admin@lists.sourceforge.net Message-ID: Mime-Version: 1.0 (generated by SEMI 1.14.3 - "Ushinoya") Content-Type: text/plain; charset=US-ASCII Return-path: Errors-To: alsa-devel-admin@lists.sourceforge.net List-Help: List-Post: List-Subscribe: , List-Unsubscribe: , List-Archive: To: alsa-devel@lists.sourceforge.net Cc: alsa-user@lists.sourceforge.net List-Id: alsa-devel@alsa-project.org Hi, i finished the extension of alsa-driver/lib for supporting 3-bytes-packed formats. the patches are found at http://www.alsa-project.org/~iwai/alsa-kernel-fmt-ext.dif.gz http://www.alsa-project.org/~iwai/alsa-driver-fmt-ext.dif.gz http://www.alsa-project.org/~iwai/alsa-lib-fmt-ext.dif.gz the patches are to the latest cvs. the patch will extend the format mask bitmap from 32 to 256 (configurable in the source code) and include conversion between 3-bytes and other conventional formats. the kernel api will be incompatible with the older one due to this change, so you'll need to update alsa-lib together with alsa-driver. the applications work without recompiling. just replace alsa-lib. the usb 24bit formats should work with this patchset, but most likely they are packed in 3-bytes, which is not supported by most applications natively. thus you'll need to use a plugin layer, i.e. specify "plughw:X,Y" as a pcm name. also, OSS emulation module doesn't support 3-bytes format. i don't think it matters, because OSS doesn't support 24bit format anyway, and all usb devices i've known support 16bit format in addition to high-bit formats. any feedbacks are appreciated. ciao, Takashi ---------------------------------------------------------------------------- Bringing you mounds of caffeinated joy >>> http://thinkgeek.com/sf <<<