The IPerChannelDbLevel interface represents a generic subunit control interface that provides per-channel control over the volume level, in decibels, of an audio stream or of a frequency band in an audio stream. A positive volume level represents gain, and a negative value represents attenuation.
Clients do not call the methods in this interface directly. Instead, this interface serves as the base interface for the following interfaces, which clients do call directly:
The IPerChannelDbLevel interface inherits from the IUnknown interface. IPerChannelDbLevel also has these types of members:
The IPerChannelDbLevel interface has these methods.
Gets the number of channels in the audio stream.
Gets the volume level, in decibels, of the specified channel.
Gets the range, in decibels, of the volume level of the specified channel.
Sets the volume level, in decibels, of the specified channel.
Sets the volume levels, in decibels, of all the channels in the audio stream.
Sets all channels in the audio stream to the same uniform volume level, in decibels.
Minimum supported client
|Windows Vista [desktop apps only]|
Minimum supported server
|Windows Server 2008 [desktop apps only]|
- DeviceTopology API
- IAudioBass Interface
- IAudioMidrange Interface
- IAudioTreble Interface
- IAudioVolumeLevel Interface