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UID title description helpviewer_keywords old-location tech.root ms.assetid ms.date ms.keywords req.header req.include-header req.target-type req.target-min-winverclnt req.target-min-winversvr req.kmdf-ver req.umdf-ver req.ddi-compliance req.unicode-ansi req.idl req.max-support req.namespace req.assembly req.type-library req.lib req.dll req.irql targetos req.typenames req.redist ms.custom f1_keywords dev_langs topic_type api_type api_location api_name
NN:devicetopology.IAudioMidrange
IAudioMidrange (devicetopology.h)
The IAudioMidrange interface provides access to a hardware midrange-level control.
IAudioMidrange
IAudioMidrange interface [Core Audio]
IAudioMidrange interface [Core Audio]
described
coreaudio.iaudiomidrange
devicetopology/IAudioMidrange
coreaudio\iaudiomidrange.htm
CoreAudio
d2d93dba-1867-4c3a-9cd1-60842bf8311d
12/05/2018
IAudioMidrange, IAudioMidrange interface [Core Audio], IAudioMidrange interface [Core Audio],described, coreaudio.iaudiomidrange, devicetopology/IAudioMidrange
devicetopology.h
Windows
Windows Vista [desktop apps only]
Windows Server 2008 [desktop apps only]
Windows
19H1
IAudioMidrange
devicetopology/IAudioMidrange
c++
APIRef
kbSyntax
COM
Devicetopology.h
IAudioMidrange

IAudioMidrange interface

-description

The IAudioMidrange interface provides access to a hardware midrange-level control. The client obtains a reference to the IAudioMidrange interface of a subunit by calling the IPart::Activate method with parameter refiid set to REFIID IID_IAudioMidrange. The call to IPart::Activate succeeds only if the subunit supports the IAudioMidrange interface. Only a subunit object that represents a hardware function for controlling the level of the mid-range frequencies in each channel will support this interface.

The IAudioMidrange interface provides per-channel controls for setting and getting the gain or attenuation level of the midrange frequencies in the audio stream. If a midrange-level hardware control can only attenuate the channels in the audio stream, then the maximum midrange level for any channel is 0 dB. If a midrange-level control can provide gain (amplification), then the maximum midrange level is greater than 0 dB.

Most Windows audio adapter drivers support the Windows Driver Model (WDM) and use kernel-streaming (KS) properties to represent the hardware control parameters in subunits (referred to as KS nodes). The IAudioMidrange interface provides convenient access to the KSPROPERTY_AUDIO_MID property of a subunit that has a subtype GUID value of KSNODETYPE_TONE. To obtain the subtype GUID of a subunit, call the IPart::GetSubType method. For more information about KS properties and KS node types, see the Windows DDK documentation.

-see-also

Core Audio Interfaces

DeviceTopology API

IPart::Activate

IPerChannelDbLevel Interface