/**
 * @license
 * Copyright 2020 Google LLC
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 *   http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */
/** Converts a Base64 encoded string to a binary string. */
export declare function decodeBase64(encoded: string): string;
/** Converts a binary string to a Base64 encoded string. */
export declare function encodeBase64(raw: string): string;
/**
 * True if and only if the Base64 conversion functions are available.
 * @internal
 */
export declare function isBase64Available(): boolean;
