export interface SynthesizeMediaPosterOptions {
    kind: 'video' | 'audio';
    src: string;
    color?: string;
    signal?: AbortSignal;
}
export declare const captureVideoPoster: (video: HTMLVideoElement | null, opts?: {
    acceptBlank?: boolean;
}) => string | null;
export declare const synthesizeVideoPoster: (src: string, signal?: AbortSignal) => Promise<string | null>;
export declare const synthesizeAudioPoster: (src: string, color?: string, signal?: AbortSignal) => Promise<string | null>;
export declare const synthesizeMediaPoster: (opts: SynthesizeMediaPosterOptions) => Promise<string | null>;