Overview

Cancel external interfering sound for Voice UI application

Discussion

DSP Concepts proprietary 2-mic Interfering Sound Canceler module. This module works in conjunction with the WOLA filterbank modules. The module has two two-channel frequency-domain audio input pins and one control pin. The first pin is two-microphone signals and the second pin is two end-fire beamforming signals. The third pin is keyword trigger flag. The module has two output pins. The first pin is mono interfering sound canceler output and the second pin is stereo interfering sound canceler output signals. If keyword trigger status is not available, connect DC source int with value of zero to the third input pin.

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The module analyzes external interfering sound and cancels it from microphone signal while preserving keyword utterances.

Type Definition

typedef struct _ModuleSb2micICv1
{
    ModuleInstanceDescriptor instance;            // Common Audio Weaver module instance structure
    FLOAT32 maxTailLength;                        // Maximum tail length in milliseconds.
    FLOAT32 maxLatency;                           // Maximum latency in milliseconds.
    FLOAT32 SR;                                   // sampling rate in Hz
    FLOAT32 tailLength;                           // Tail length, in milliseconds.
    FLOAT32 latency;                              // Latency, in milliseconds.
    INT32 aecMaxTaps;                             // Maximum tail length in samples.
    INT32 aecNumTaps;                             // tail length in samples.
    INT32 maxBlockDelay;                          // Maximum block delay.
    INT32 blockDelay;                             // block delay.
    INT32 blockExtractStartIndex;                 // Block extract start index.
    INT32 blockExtractEndIndex;                   // Block extract end index.
    // +35 private module(s)                     
} ModuleSb2micICv1Class;

Variables

Properties

Pins

Input Pins

Name: micIn

Description: Audio input

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Sample rate range: Unrestricted

Complex support: Real

Output Pins

Name: monoOut

Description: Audio input

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Description: Audio input

Data type: float

Scratch Pins

Channel count: 1

Block size: 32

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Block size: 1

Sample rate: 48000

MATLAB Usage

File Name: sb_2mic_IC_v1_module.m

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