import { PorcupineInputOptions, PorcupineOptions } from './types';
export default class Porcupine {
    private _pvPorcupine;
    private _handle;
    private readonly _version;
    private readonly _sampleRate;
    private readonly _frameLength;
    /**
     * Creates an instance of Porcupine.
     * @param {string} accessKey AccessKey obtained from Picovoice Console (https://console.picovoice.ai/).
     * @param {Array} keywords Absolute paths to keyword model files (`.ppn`).
     * @param {Array} sensitivities Sensitivity values for detecting keywords.
     * Each value should be a number within [0, 1]. A higher sensitivity results in fewer misses
     * at the cost of increasing the false alarm rate.
     * @param options Optional configuration arguments.
     * @param {string} options.modelPath Path to the Porcupine model (.pv extension)
     * @param {string} options.device String representation of the device (e.g., CPU or GPU) to use for inference.
     * If set to `best`, the most suitable device is selected automatically. If set to `gpu`, the engine uses the
     * first available GPU device. To select a specific GPU device, set this argument to `gpu:${GPU_INDEX}`, where
     * `${GPU_INDEX}` is the index of the target GPU. If set to `cpu`, the engine will run on the CPU with the
     * default number of threads. To specify the number of threads, set this argument to `cpu:${NUM_THREADS}`,
     * where `${NUM_THREADS}` is the desired number of threads.
     * @param {string} options.libraryPath Path to the Porcupine library (.node extension)
     */
    constructor(accessKey: string, keywords: string[], sensitivities: number[], options?: PorcupineOptions);
    /**
     * @returns number of audio samples per frame (i.e. the length of the array provided to the process function)
     * @see {@link process}
     */
    get frameLength(): number;
    /**
     * @returns the audio sampling rate accepted by Porcupine
     */
    get sampleRate(): number;
    /**
     * @returns the version of the Porcupine engine
     */
    get version(): string;
    /**
     * Process a frame of pcm audio.
     *
     * @param {Array} frame of mono, 16-bit, linear-encoded PCM audio.
     * The specific array length can be attained by calling `.frameLength`.
     * The incoming audio needs to have a sample rate equal to `.sampleRate` and be 16-bit linearly-encoded.
     * Porcupine operates on single-channel audio.
     * @returns {number} Index of observed keyword at the end of the current frame.
     * Indexing is 0-based and matches the ordering of keyword models provided to the constructor.
     * If no keyword is detected then it returns -1.
     */
    process(frame: Int16Array): number;
    /**
     * Releases the resources acquired by Porcupine.
     *
     * Be sure to call this when finished with the instance
     * to reclaim the memory that was allocated by the C library.
     */
    release(): void;
    /**
     * Lists all available devices that Porcupine can use for inference. Each entry in the list can be the `device` argument
     * of the constructor.
     *
     * @returns List of all available devices that Porcupine can use for inference.
     */
    static listAvailableDevices(options?: PorcupineInputOptions): string[];
    private handlePvStatus;
}
//# sourceMappingURL=porcupine.d.ts.map