IRenderingControl::GetVolumeDB (Windows Embedded CE 6.0)

1/6/2010

This method returns the current volume, in units of 1/256 of a decibel, for the specified channel in this RenderingControl instance.

Syntax

virtual DWORD GetVolumeDB(
  LPCWSTR pszChannel,
  short* pVolumeDB
) = 0;

Parameters

• pszChannel
  [in] Audio channel to examine. For example, Master, LF (left front), RF (right front), and so on. Corresponds to the A_ARG_TYPE_Channel state variable.

• pVolumeDB
  [in, out] Decibel volume setting for the specified channel in this RenderingControl instance. Each increment is 1/256th of a decibel. You can retrieve the range of allowed values using IRenderingControl::GetVolumeDBRange. Corresponds to the VolumeDB state variable.

Return Value

Custom implementations can return appropriate error codes. Should return SUCCESS_AV if the method succeeds. Otherwise, should return an error code defined in WinError.h or UPnP.h, or one of the UPnP AV-specific return values specified in UPnPAVError, especially the following errors documented for this action in the RenderingControl DCP documentation:

• ERROR_AV_UPNP_ACTION_FAILED
• ERROR_AV_UPNP_RC_INVALID_INSTANCE_ID

Remarks

This method corresponds to the RenderingControl service's GetVolumeDB action.

The RenderingControl service does not require that this method be implemented. The IRenderingControlImpl class therefore overrides this method to return ERROR_AV_UPNP_INVALID_ACTION.

For more information about the actions in the RenderingControl service, see UPnP AV DCP Documentation.

Requirements

See Also

Reference

IRenderingControl
IRenderingControl::GetVolumeDBRange
IRenderingControlImpl
UPnPAVError