KSAUDIO_MIXLEVEL structure (ksmedia.h)

The KSAUDIO_MIXLEVEL structure specifies the mixing level of an input-output path in a supermixer node (KSNODETYPE_SUPERMIX).

Syntax

typedef struct {
  BOOL Mute;
  LONG Level;
} KSAUDIO_MIXLEVEL, *PKSAUDIO_MIXLEVEL;

Members

Mute

Specifies whether the input channel is muted (not mixed) as it flows into the output channel. A value of TRUE indicates that the channel is muted. A value of FALSE indicates that the channel's mix level is specified by the Level member.

Level

Specifies the mix level that is applied to the input channel as it flows into the output channel. For more information, see the following Remarks section.

Remarks

A KSAUDIO_MIXLEVEL structure specifies the volume level of a particular data path from one input channel of a supermixer node to an output channel of the same node. An array of these structures is needed to specify the volume levels for all the input-output paths through a supermixer node.

To specify the mixing levels of all paths through a supermixer node with m input channels and n output channels requires a mix-level table consisting of an m x n array of KSAUDIO_MIXLEVEL structures. This table is used to set or get the data value for the KSPROPERTY_AUDIO_MIX_LEVEL_TABLE property.

The mix-level value in the Level member uses the following scale:

-2147483648 is -Infinity decibels (attenuation),

-2147483647 is -32767.99998474 decibels (attenuation), and

+2147483647 is +32767.99998474 decibels (gain).

A decibel range represented by integer values -2147483648 to +2147483647, where

This scale has a resolution of 1/65536 decibel.

Requirements

See also

KSNODETYPE_SUPERMIX

KSPROPERTY_AUDIO_MIX_LEVEL_CAPS

KSPROPERTY_AUDIO_MIX_LEVEL_TABLE