Audio Software Components

The following diagram illustrates the relationship of the major Windows NT audio software components.

The components in the diagram include:

• Application

  Any user-mode, Win32-based application that calls the audio API functions described in the Win32 SDK.

• winmm.dll

  A dynamic-link library that exports the waveform, MIDI, mixer, and auxiliary audio functions described in the Win32 SDK.

• msacm32.dll

  A dynamic-link library that contains the Audio Compression Manager (ACM). For information about the ACM and ACM drivers, see Audio Compression Manager Drivers.

• midimap.dll

  The Windows NT MIDI Mapper.

• msacm32.drv

  The Windows NT Wave Mapper.

• User-mode drivers

  Dynamic-link libraries that communicate with kernel-mode drivers (or sometimes other user-mode drivers).

• ACM drivers

  Dynamic-link libraries under the control of the ACM. See msacm32.dll, above.

• drvlib.lib

  A library used as a basis for user-mode audio drivers. For more information, see Using drvlib.lib.

• Kernel-mode drivers

  Kernel-mode code that communicates with the Windows NT Executive in order to access device hardware.

• soundlib.lib

  A library used as a basis for kernel-mode audio drivers. For more information, see Using soundlib.lib.