Windows 10 noise suppression and acoustic echo cancellation

Windows 10 noise suppression and acoustic echo cancellation driver#
Windows 10 noise suppression and acoustic echo cancellation software#
Windows 10 noise suppression and acoustic echo cancellation windows#

These restrictions reflect fundamental assumptions in the design and implementation of the AEC system filter. The preceding requirements apply to all kernel-streaming audio filter graphs that incorporate capture effects that are implemented in Aec.sys. AEC has no way of canceling (and no effect on) echoes from either a radio or a non-AEC channel. Echoes in a non-AEC audio channel are functionally equivalent to echoes in the audio that is playing on a radio in the office next to your computer. Audio that is output through channels that do not pass through AEC is not echo-canceled. Performing any nonlinear or time-varying signal processing in either of these locations prevents AEC from canceling the echo in the capture signal.ДЄEC filtering cancels only echoes coming from the AEC-filtered channels in your computer. This restriction is necessary to ensure that all audio that is played by the rendering device can be canceled out of the capture stream by the AEC system filter.ДЄny signal processing that is done before the AEC or NS node on the capture side of the graph or after the AEC or NS node on the render side must be linear time-invariant.

Windows 10 noise suppression and acoustic echo cancellation software#

All mixing of streams is done in software emulation by the KMixer system driver.

Windows 10 noise suppression and acoustic echo cancellation driver#

When the AEC system filter is used, the SysAudio system driver turns off hardware acceleration for mixing, sample-rate conversion, 3D spatialization, and so on. The AEC system filter correctly handles mismatches between the clocks for the capture and render streams, and separate devices can be used for capture and rendering.

Windows 10 noise suppression and acoustic echo cancellation windows#

In Windows XP SP1, Windows Server 2003, and later, this limitation does not exist. Only monophonic streams can be processed by the render side. If the capture stream is multichannel (for example, two-channel stereo), all channels other than the first are ignored (and discarded).

The AEC and NS nodes (see figure in Exposing Hardware-Accelerated Capture Effects) can handle only monophonic streams. Note that the render-out pin does not support a sample rate of 8 kHz.

(The order of preference is based on processing time and audio quality.) The sample rate at the render-out pin can be (in order of preference) 16 kHz, 48 kHz, or 44.1 kHz. The sample rate at the capture-in pin can be (in order of preference) 16 kHz, 48 kHz, 44.1 kHz, or 8 kHz. In Windows XP SP1, Windows Server 2003, and later, the AEC system filter's capture-out and render-in pins (see the following figure) must have the same sample rate, but the sample rates at the capture-in and render-out pins can each be selected independently of the other pins. The input and output streams are source-rate converted as necessary.

The AEC system filter performs all internal processing at 16 kHz. The bit depth must be 16 bits for the capture stream and 8 or 16 bits for the render stream. The AEC system filter can connect only to pins that handle PCM data formats.

Constraints Imposed by AEC System FilterДЄn audio filter graph that incorporates a capture effect that is implemented in the AEC system filter is subject to the following restrictions: For information about how DirectSoundCapture applications enable use of the AEC system filter, see the Microsoft Windows SDK documentation. This filter is a standard operating-system component in Windows XP and later. The AEC system filter (Aec.sys) implements the acoustic echo cancellation (AEC) and noise suppression (NS) algorithms in software.