import { ElementRef, EventEmitter, OnChanges, OnDestroy, SimpleChanges } from '@angular/core';
export declare class LazyImageDirective implements OnChanges, OnDestroy {
    private el;
    private io;
    src: string;
    root: Element;
    rootMargin: string;
    threshold: number | number[];
    willLoad: EventEmitter<void>;
    srcAttr: string;
    decodingAttr: string;
    readonly visibilityStyle: string;
    constructor(el: ElementRef<Element>);
    ngOnChanges(changes: SimpleChanges): void;
    ngOnDestroy(): void;
    private canLazyLoad;
    private load;
    private lazyLoadImage;
    private loadImage;
    private addIO;
    private removeIO;
}