IChannelAudioVolume::GetAllVolumes method (audioclient.h)

Article
02/22/2024

The GetAllVolumes method retrieves the volume levels for all the channels in the audio session.

Syntax

HRESULT GetAllVolumes(
  [in]  UINT32 dwCount,
  [out] float  *pfVolumes
);

Parameters

[in] dwCount

The number of elements in the pfVolumes array. The dwCount parameter must equal the number of channels in the stream format for the audio session. To get the number of channels, call the IChannelAudioVolume::GetChannelCount method.

[out] pfVolumes

Pointer to an array of volume levels for the channels in the audio session. This parameter points to a caller-allocated float array into which the method writes the volume levels for the individual channels. Volume levels are in the range 0.0 to 1.0.

Return value

If the method succeeds, it returns S_OK. If it fails, possible return codes include, but are not limited to, the values shown in the following table.

Return code	Description
E_INVALIDARG	Parameter dwCount does not equal the number of channels in the stream format for the audio session.
E_POINTER	Parameter pfVolumes is NULL.
AUDCLNT_E_DEVICE_INVALIDATED	The audio endpoint device has been unplugged, or the audio hardware or associated hardware resources have been reconfigured, disabled, removed, or otherwise made unavailable for use.
AUDCLNT_E_SERVICE_NOT_RUNNING	The Windows audio service is not running.

Remarks

Clients can call the IChannelAudioVolume::SetAllVolumes or IChannelAudioVolume::SetChannelVolume method to set the per-channel volume levels in an audio session.

Requirements

Requirement	Value
Minimum supported client	Windows Vista [desktop apps only]
Minimum supported server	Windows Server 2008 [desktop apps only]
Target Platform	Windows
Header	audioclient.h