/**
 * Validates if a string is a valid Base64 encoded string
 *
 * @param base64String - String to validate
 * @returns true if valid Base64
 *
 * @example
 * ```typescript
 * isValidBase64Image('SGVsbG8gV29ybGQ='); // true
 * isValidBase64Image('not-base64!@#'); // false
 * ```
 */
export declare function isValidBase64Image(base64String: string): boolean;
/**
 * Strips Base64 data URL prefix if present
 *
 * Removes 'data:image/...;base64,' prefix from data URLs.
 *
 * @param base64String - Base64 string (may include data URL prefix)
 * @returns Clean Base64 string without prefix
 *
 * @example
 * ```typescript
 * stripDataUrlPrefix('data:image/png;base64,iVBORw0KG...');
 * // Returns: 'iVBORw0KG...'
 * ```
 */
export declare function stripDataUrlPrefix(base64String: string): string;
/**
 * Reads an image file and converts it to Base64
 *
 * @param filePath - Path to image file
 * @returns Promise resolving to Base64 encoded image
 * @throws {ValidationError} If file cannot be read
 *
 * @example
 * ```typescript
 * const base64 = await imageFileToBase64('./image.jpg');
 * ```
 */
export declare function imageFileToBase64(filePath: string): Promise<string>;
//# sourceMappingURL=image.d.ts.map