次の方法で共有

WODM_SETVOLUME (Compact 2013)

  • [アーティクル]

3/26/2014

This message is used in an MMDRV_MESSAGE_PARAMS structure passed to the WAV_IOControl function to request a waveform output driver to set the playback rate multiplier value for the specified device.

Parameters

  • uDeviceId
    Device identifier - 0, 1, 2, and so on - for the target device.
  • uMsg
    Specifies this message.
  • dwUser
    Specifies a device instance identifier.
  • dwParam1
    Specifies a DWORD containing the volume setting.
  • dwParam2
    Not used.

Return Values

MMSYSERR_NOERROR indicates success. Otherwise, the driver returns one of the MMSYSERR or WAVEERR error values declared in the Mmsystem.h header file.

Remarks

The waveform API manager sends this message by calling the audio driver's WAV_IOControl entry point through the DeviceIoControl function. Support for this message by drivers is optional. However, if the driver supports this message, it must support WODM_GETVOLUME. The following table shows which bytes in dwParam1 indicate the volume settings for both stereo and monaural audio channels.

Channel

Portion of dwParam1 used

Left channel

Low WORD

Right channel

High WORD

Single channel

Low WORD

A value of 0 is silence; 0xFFFF is full volume.

Requirements

Header

mmddk.h

See Also

Reference

Waveform Output Driver Messages
MMDRV_MESSAGE_PARAMS
WAV_IOControl