web-voice-detection/dist/common/frame-processor.d.ts

A WebAssembly-powered Voice Activity Detection library for the browser.

import { Message } from "./messages";
import { SpeechProbabilities } from "./models";
export type FrameProcessorOptions = {
    /**
     * Threshold over which values returned by the ONNXModel model
     * will be considered as positively indicating speech.
     * The ONNXModel model is run on each frame.
     * This number should be between 0 and 1.
     */
    positiveSpeechThreshold: number;
    /**
     * Threshold under which values returned by the ONNXModel model
     * will be considered as indicating an absence of speech.
     * Note that the creators of the ONNXModel have historically
     * set this number at 0.15 less than `positiveSpeechThreshold`.
     */
    negativeSpeechThreshold: number;
    /**
     * After a detected value under the `negativeSpeechThreshold` is observed,
     * the algorithm will wait `redemptionFrames` frames before running `onSpeechEnd`.
     * If the model returns a value over `positiveSpeechThreshold` during this
     * grace period, then the algorithm will consider the previously-detected
     * "speech end" as having been a false negative.
     */
    redemptionFrames: number;
    /**
     * Number of audio samples (under a sample rate of 16000) to comprise
     * one "frame" to feed to the ONNXModel model. The `frame` serves
     * as a unit of measurement of lengths of audio segments and many other
     * parameters are defined in terms of rames. The authors of the
     * ONNX model offer the following warning:
     *
     * > WARNING! ONNXModel models were trained using
     * > 512, 1024, 1536 samples for 16000 sample rate
     * > and 256, 512, 768 samples for 8000 sample rate.
     * > Values other than these may affect model perfomance!
     *
     * In this context, audio fed to the model always has sample rate 16000.
     * It is probably a good idea to leave this at 1536.
     */
    frameSamples: number;
    /**
     * Number of frames to prepend to the audio
     * segment that will be passed to `onSpeechEnd`.
     */
    preSpeechPadFrames: number;
    /**
     * If an audio segment is detected as a speech segment according to initial algorithm
     * but it has fewer than `minSpeechFrames`,
     * it will be discarded and `onMisfire` will be run instead of `onSpeechEnd`.
     */
    minSpeechFrames: number;
    /**
     * If true, when the user pauses the detection, it may trigger `onSpeechEnd`.
     */
    submitUserSpeechOnPause: boolean;
};
export declare const defaultFrameProcessorOptions: FrameProcessorOptions;
export declare function validateOptions(options: FrameProcessorOptions): void;
export type FrameProcessorInterface = {
    resume: () => void;
    process: (arr: Float32Array) => Promise<{
        probs?: SpeechProbabilities;
        msg?: Message;
        audio?: Float32Array;
    }>;
    endSegment: () => {
        msg?: Message;
        audio?: Float32Array;
    };
};
export declare class FrameProcessor implements FrameProcessorInterface {
    modelProcessFunc: (frame: Float32Array) => Promise<SpeechProbabilities>;
    modelResetFunc: () => any;
    options: FrameProcessorOptions;
    speaking: boolean;
    audioBuffer: {
        frame: Float32Array;
        isSpeech: boolean;
    }[];
    redemptionCounter: number;
    active: boolean;
    constructor(modelProcessFunc: (frame: Float32Array) => Promise<SpeechProbabilities>, modelResetFunc: () => any, options: FrameProcessorOptions);
    reset: () => void;
    pause: () => {
        msg: Message;
        audio: Float32Array;
    } | {
        msg: Message;
        audio?: undefined;
    } | {
        msg?: undefined;
        audio?: undefined;
    };
    resume: () => void;
    endSegment: () => {
        msg: Message;
        audio: Float32Array;
    } | {
        msg: Message;
        audio?: undefined;
    } | {
        msg?: undefined;
        audio?: undefined;
    };
    process: (frame: Float32Array) => Promise<{
        probs?: undefined;
        msg?: undefined;
        audio?: undefined;
    } | {
        probs: SpeechProbabilities;
        msg: Message;
        audio?: undefined;
    } | {
        probs: SpeechProbabilities;
        msg: Message;
        audio: Float32Array;
    } | {
        probs: SpeechProbabilities;
        msg?: undefined;
        audio?: undefined;
    }>;
}