IAMAudioInputMixer Interface

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Microsoft DirectShow 9.0

IAMAudioInputMixer Interface

The IAMAudioInputMixer interface controls audio capture properties, such as panning and loudness; and enables or disables specific audio inputs, such as the line in or the microphone.

The Audio Capture filter exposes this interface on each input pin, as well as on the filter itself. The input pins on the Audio Capture Filter represent physical hardware connections; they are not connected to other DirectShow filters. The pin name indicates the input type; for example, "Line In" or "Microphone." Use the IAMAudioInputMixer interface as follows:

  • To control the settings on a particular input, use the interface on the pin.
  • To set the overall properties when multiple inputs are enabled, use the interface on the filter.
  • To enable or disable an input, call that pin's IAMAudioInputMixer::put_Enable method.

Some methods on this interface might fail, depening on the capabilities of the underlying hardware.

Filter Developers: Implement this interface on each input pin of an audio capture filter. You can also implement this interface on the audio capture filter itself to control the overall audio settings after mixing.

In addition to the methods inherited from IUnknown, the IAMAudioInputMixer interface exposes the following methods.

Method Description
put_Enable Enables or disables an input.
get_Enable Queries whether an input is enabled.
put_Mono Combines all channels of an input into a mono signal.
get_Mono Queries whether all the channels of an input are combined into a mono signal.
put_MixLevel Sets the recording level.
get_MixLevel Retrieves the recording level.
put_Pan Sets the pan level.
get_Pan Retrieves the pan level.
put_Loudness Sets the loudness control.
get_Loudness Retrieves the loudness control setting.
put_Treble Sets the treble equalization.
get_Treble Retrieves the treble equalization.
get_TrebleRange Retrieves the treble range.
put_Bass Sets the bass equalization.
get_Bass Retrieves the bass equalization.
get_BassRange Retrieves the bass range.

Requirements

Header: Declared in Strmif.h; include Dshow.h.

Library: Use Strmiids.lib.