/**
 * Metadata Extractor Module
 * Extracts Open Graph and Twitter Card metadata from URLs
 */
import { ExtractedMetadata } from '../types';
/**
 * Extract metadata from a given URL
 * @param url - The URL to extract metadata from
 * @returns Extracted metadata object
 */
export declare function extractMetadata(url: string): Promise<ExtractedMetadata>;
/**
 * Fetch image from URL and return as buffer
 * @param imageUrl - URL of the image to fetch
 * @returns Image buffer
 */
export declare function fetchImage(imageUrl: string): Promise<Buffer>;
/**
 * Validate metadata to ensure required fields are present
 */
export declare function validateMetadata(metadata: ExtractedMetadata): boolean;
/**
 * Apply fallback values to incomplete metadata
 */
export declare function applyFallbacks(metadata: Partial<ExtractedMetadata>, url: string): ExtractedMetadata;