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- /*
- * base64-arraybuffer
- * https://github.com/niklasvh/base64-arraybuffer
- *
- * Copyright (c) 2012 Niklas von Hertzen
- * Licensed under the MIT license.
- */
- (function(chars){
- "use strict";
-
- exports.encode = function(arraybuffer) {
- var bytes = new Uint8Array(arraybuffer),
- i, len = bytes.length, base64 = "";
-
- for (i = 0; i < len; i+=3) {
- base64 += chars[bytes[i] >> 2];
- base64 += chars[((bytes[i] & 3) << 4) | (bytes[i + 1] >> 4)];
- base64 += chars[((bytes[i + 1] & 15) << 2) | (bytes[i + 2] >> 6)];
- base64 += chars[bytes[i + 2] & 63];
- }
-
- if ((len % 3) === 2) {
- base64 = base64.substring(0, base64.length - 1) + "=";
- } else if (len % 3 === 1) {
- base64 = base64.substring(0, base64.length - 2) + "==";
- }
-
- return base64;
- };
-
- exports.decode = function(base64) {
- var bufferLength = base64.length * 0.75,
- len = base64.length, i, p = 0,
- encoded1, encoded2, encoded3, encoded4;
-
- if (base64[base64.length - 1] === "=") {
- bufferLength--;
- if (base64[base64.length - 2] === "=") {
- bufferLength--;
- }
- }
-
- var arraybuffer = new ArrayBuffer(bufferLength),
- bytes = new Uint8Array(arraybuffer);
-
- for (i = 0; i < len; i+=4) {
- encoded1 = chars.indexOf(base64[i]);
- encoded2 = chars.indexOf(base64[i+1]);
- encoded3 = chars.indexOf(base64[i+2]);
- encoded4 = chars.indexOf(base64[i+3]);
-
- bytes[p++] = (encoded1 << 2) | (encoded2 >> 4);
- bytes[p++] = ((encoded2 & 15) << 4) | (encoded3 >> 2);
- bytes[p++] = ((encoded3 & 3) << 6) | (encoded4 & 63);
- }
-
- return arraybuffer;
- };
- })("ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789+/");
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