export declare class Base64Utils {
    /**
     * Create a Base64-encoded string from a given input. To allow unicode characters
     * the input will be converted into a binary string before encoding.
     *
     * @param input String input
     * @return Base64 encoded binary representation of the input
     */
    static toBase64(input: string): string;
    /**
     * Decode a string of base64 encoded data
     *
     * @param base64 Base64 encoded string
     */
    static fromBase64(base64: string): string;
}