import Device from './Device';
/**
 * A device that applies processing to another device.
 */
export default interface VideoTransformDevice {
    /**
     * `stop` should be called  to free any resources associated with the device.
     * It must be called if `applyProcessors` is ever called.
     */
    stop(): Promise<void>;
    /**
     * Returns the inner {@link Device} that the device controller should select as active video device.
     */
    intrinsicDevice(): Promise<Device>;
    /**
     * Starts processing the input `MediaStream` and returns the output `MediaStream`.
     */
    applyProcessors(mediaStream?: MediaStream): Promise<MediaStream>;
    /**
     * `outputMediaStream` is generated after processors are applied. It will be auto-released after `stop` is called.
     */
    readonly outputMediaStream: MediaStream;
}
/**
 * `isVideoTransformDevice` is a type guard for {@link VideoTransformDevice}.
 *
 * @param device the value to check.
 */
export declare function isVideoTransformDevice(device: unknown): device is VideoTransformDevice;