import { Layout, RequestKeyFrame, StopStream } from './ParticipantLayout';
export declare const REQUEST_KEY_FRAME_CODE = "kf";
export declare function isStopStreaming(layout: Layout | StopStream | RequestKeyFrame): layout is StopStream;
export declare function isRequestKeyFrame(layout: Layout | StopStream | RequestKeyFrame): layout is RequestKeyFrame;
export declare function layoutToString(layout: Layout | StopStream | RequestKeyFrame): string;