import React from 'react';
export interface FastImageCommonProps {
    /**
     * Media is surrounded by two spans for positioning.
     * This class will be added to the outer span.
     */
    className?: string;
    /**
     * Media is surrounded by two spans for positioning.
     * This class will be added to the outer span.
     * This class will be added when the image is visible and added to the DOM.
     */
    classNameVisible?: string;
    /**
     * Media is surrounded by two spans for positioning.
     * This class will be added to the inner span.
     */
    classNameContainer?: string;
    /**
     * Media is surrounded by two spans for positioning.
     * This class will be added to the inner span.
     * This class will be added when the image is visible and added to the DOM.
     */
    classNameContainerVisible?: string;
    /**
     * The css class that will go on the media element (img or video).
     */
    classNameMedia?: string;
    /**
     * The css class that will go on the media element (img or video).
     * This class will be added when the image is visible and added to the DOM.
     */
    classNameMediaVisible?: string;
    /**
     * Whether or not to wait for the image to enter the viewport to load it.
     */
    lazy?: boolean;
    /**
     * Determines when the media will be loaded.
     * e.g. 200px
     */
    lazyLoadMargin?: string;
    /**
     * The original width of the media.
     */
    width: number;
    /**
     * The original height of the media.
     */
    height: number;
    onLoad?: Function;
    onAddedToDOM?: Function;
}
export interface FastImageImageBestProps extends FastImageCommonProps {
    imgAlt: string;
    imgSizes: string;
    imgSrc: string;
    imgSrcSet: string;
    imgBase64: string;
    imgWebPSrc: string;
    imgWebPSrcSet: string;
}
export interface FastImageVideoBestProps extends FastImageCommonProps {
    videoSrc: string;
    videoPosterSrc: string;
    videoPosterWebPSrc: string;
    videoPosterBase64: string;
}
export declare type FastImageBestProps = FastImageImageBestProps & FastImageVideoBestProps;
export declare type FastImageProps = Partial<FastImageImageBestProps & FastImageVideoBestProps>;
export declare class FastImage extends React.PureComponent<FastImageProps> {
    static defaultProps: FastImageProps;
    render(): JSX.Element | null;
}