import { AfterViewInit, ChangeDetectorRef, ElementRef, OnChanges, OnDestroy, OnInit, TemplateRef, ViewContainerRef } from '@angular/core';
import { WindowRef } from './utils/window.reference';
export interface ImageSource {
    media: string;
    url: string;
}
export interface ImageMetadata {
    keywords: string;
    name: string;
    url: string;
}
export declare type StretchStrategy = 'crop' | 'stretch' | 'original';
export declare class LazyImageComponent implements AfterViewInit, OnChanges, OnDestroy, OnInit {
    private readonly cdRef;
    private readonly el;
    private readonly viewContainer;
    private readonly windowRef;
    sources: ImageSource[];
    metadata: ImageMetadata;
    loadingTpl: TemplateRef<any>;
    errorTpl: TemplateRef<any>;
    canvasRatio: number;
    maxCropPercentage: number;
    stretchStrategy: StretchStrategy;
    shouldFallbackToImgTag: boolean;
    loadingTplRef: TemplateRef<any>;
    errorTplRef: TemplateRef<any>;
    wasInViewport: boolean;
    canvasWidth: number;
    canvasHeight: number;
    matchedImageUrl: string;
    backgroundString: string;
    stretchState: StretchStrategy;
    loading: boolean;
    errorOccurred: boolean;
    disableLazyLoading: boolean;
    private imageElement;
    private scrollBufferSize;
    private verticalPosition;
    private imageWidth;
    private imageHeight;
    private errorEventListener;
    private loadEventListener;
    private image;
    constructor(cdRef: ChangeDetectorRef, el: ElementRef, viewContainer: ViewContainerRef, windowRef: WindowRef);
    ngOnInit(): void;
    ngOnDestroy(): void;
    ngAfterViewInit(): void;
    ngOnChanges(): void;
    updatePositioning(): void;
    updateVisibility(event?: Event): void;
    private renderTemplates;
    private calculateCanvasSize;
    private determineBackground;
    private withinCropThreshold;
    private updateBackground;
    private updateStretchState;
    private updateResponsiveImage;
    private validateInputs;
}