unified audio model

From: A. Thirupathi Reddy (anonymous_at_discussions.microsoft.com)
Date: 07/08/04 

Date: Wed, 7 Jul 2004 20:25:57 -0700

Hello,
  This conversion is done by Software Mixer.The software
mixer will convert all audio streams (from the
applications) to a common format(16-bit stereo, 44.1 KHz
or the registry specified value) combine them into a
single stream, and pass that to the driver. This is due
to the fact that audio hardware can be configured for one
format at a time and that format is the output format of
the software mixer. The settings for Software Mixer are
located under the following registry key
[HKEY_LOCAL_MACHINE\Audio\SoftwareMixer]
  This is also depends on the number of streams that UAM
driver is exposing to the system (in WODM_GETEXTDEVCAPS).
Suppose UAM driver says it can mix 3 streams in the
hardware, then first two streams are directly allocated to
the applications, third one is reserved for the software
mixer. So third stream is set to use the output format of
the software mixer (it is not the applications format).

A. Thirupathi Reddy

>-----Original Message-----
>hi all,
>
>i am working on an audio driver based on unified audio
model.
>i see some mismatch in the .wav format being passed down
to the audio driver
>from
>waveapi manager.
>
>for example:
>when i run the .wav file with format mono 8bit 11KHz
using the application
>wavplay.exe
>the format passed to my audio driver through the waveapi
manager is
>different,
>stereo 16bit 44KHz.
>
>regards
>neo
>
>
>.
>

Relevant Pages

  • Re: Dump does work! -was: Problem playing mms stream using mplayer or other players
    ... The audio file was written in each case, ... But dump _can_ be made to work on these two streams! ... ASF file format detected. ...
    (alt.os.linux.suse)
  • Dump does work! -was: Problem playing mms stream using mplayer or other players
    ... The audio file was written in each case, ... But dump _can_ be made to work on these two streams! ... ASF file format detected. ...
    (alt.os.linux.suse)
  • HW mixer API use
    ... We have a DSP based hardware mixer in our audio device which can mix multiple audio streams. ... How would my application which would be using handles from Wave API can use this Mixer API for effects etc. ...
    (microsoft.public.win32.programmer.mmedia)
  • HW mixer API use
    ... We have a DSP based hardware mixer in our audio device which can mix multiple audio streams. ... How would my application which would be using handles from Wave API can use this Mixer API for effects etc. ...
    (microsoft.public.windowsce.embedded)
  • HW mixer API use
    ... We have a DSP based hardware mixer in our audio device which can mix multiple audio streams. ... How would my application which would be using handles from Wave API can use this Mixer API for effects etc. ...
    (microsoft.public.windowsce.app.development)