| /* |
| * |
| * Licensed to the Apache Software Foundation (ASF) under one |
| * or more contributor license agreements. See the NOTICE file |
| * distributed with this work for additional information |
| * regarding copyright ownership. The ASF licenses this file |
| * to you 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. |
| * |
| */ |
| |
| var base64 = exports; |
| |
| base64.fromArrayBuffer = function(arrayBuffer) { |
| var array = new Uint8Array(arrayBuffer); |
| return uint8ToBase64(array); |
| }; |
| |
| //------------------------------------------------------------------------------ |
| |
| /* This code is based on the performance tests at http://jsperf.com/b64tests |
| * This 12-bit-at-a-time algorithm was the best performing version on all |
| * platforms tested. |
| */ |
| |
| var b64_6bit = "ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789+/"; |
| var b64_12bit; |
| |
| var b64_12bitTable = function() { |
| b64_12bit = []; |
| for (var i=0; i<64; i++) { |
| for (var j=0; j<64; j++) { |
| b64_12bit[i*64+j] = b64_6bit[i] + b64_6bit[j]; |
| } |
| } |
| b64_12bitTable = function() { return b64_12bit; }; |
| return b64_12bit; |
| }; |
| |
| function uint8ToBase64(rawData) { |
| var numBytes = rawData.byteLength; |
| var output=""; |
| var segment; |
| var table = b64_12bitTable(); |
| for (var i=0;i<numBytes-2;i+=3) { |
| segment = (rawData[i] << 16) + (rawData[i+1] << 8) + rawData[i+2]; |
| output += table[segment >> 12]; |
| output += table[segment & 0xfff]; |
| } |
| if (numBytes - i == 2) { |
| segment = (rawData[i] << 16) + (rawData[i+1] << 8); |
| output += table[segment >> 12]; |
| output += b64_6bit[(segment & 0xfff) >> 6]; |
| output += '='; |
| } else if (numBytes - i == 1) { |
| segment = (rawData[i] << 16); |
| output += table[segment >> 12]; |
| output += '=='; |
| } |
| return output; |
| } |