MM_WOM_SETSECONDARYGAINLIMIT (Windows Embedded CE 6.0)

1/6/2010

This message places a limit on the maximum volume for all streams associated with an attenuation class and scales the streams' volumes accordingly. For more information see Attenuation Classes.

Syntax

MM_WOM_SETSECONDARYGAINLIMIT
    wParam = (DWORD) dwClass
    lParam = (DWORD) dwLimit

Parameters

• dwClass
  A DWORD value that identifies the attenuation class that should be limited. You can set this parameter to 0, 1, 2, or 3. The default attenuation class value for new waveform audio streams is 0.

• dwLimit
  A DWORD value that sets the new volume limit for the attenuation class identified by dwClass. The default limit for an attenuation class is 0xFFFF, which corresponds to full volume.

Return Value

None.

Remarks

This message limits the maximum volume of all streams associated with the attenuation class dwClass to the value specified in dwLimit. When the new limit is set, the waveform audio API scales the current stream volumes according to the new limit value. For example, if the full volume range is 0 to -100dB, and the class's current limit is set to 0x8000 (mid-scale), then all streams in that class will have their volume controls scaled to lie in the range of -50dB to -100dB. In this scenario a stream with a volume of 0x8000 will have -75dB of gain. Initially, the default limit is 0xFFFF, which leaves the stream unattenuated.

Requirements

See Also

Reference

Waveform Audio Messages
waveOutMessage

Concepts

Attenuation Classes