import { VideoRenderParams } from './utils';
export declare class CameraPreviewTaskManager {
    private taskMap;
    protected logger: import("agora-foundation/lib/logger").Logger;
    constructor();
    addTask(view: HTMLElement, options: VideoRenderParams): HTMLElement;
    private doRender;
    executeSingleTask(view: HTMLElement): boolean;
    executeAllTasks(): void;
    /**
     * 执行指定 sourceId（deviceId）对应的所有 task
     * 用于多摄像头场景下，只执行特定设备的 preview task
     */
    executeTasksBySourceId(sourceId: string): Boolean;
    getTaskOptions(view: HTMLElement): VideoRenderParams | undefined;
    deleteTask(view: HTMLElement): void;
    clearAllTasks(): void;
    getTaskCount(): number;
    release(): void;
}