| /* |
| * 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 Guacamole = Guacamole || {}; |
| |
| /** |
| * A description of the format of raw PCM audio, such as that used by |
| * Guacamole.RawAudioPlayer and Guacamole.RawAudioRecorder. This object |
| * describes the number of bytes per sample, the number of channels, and the |
| * overall sample rate. |
| * |
| * @constructor |
| * @param {Guacamole.RawAudioFormat|Object} template |
| * The object whose properties should be copied into the corresponding |
| * properties of the new Guacamole.RawAudioFormat. |
| */ |
| Guacamole.RawAudioFormat = function RawAudioFormat(template) { |
| |
| /** |
| * The number of bytes in each sample of audio data. This value is |
| * independent of the number of channels. |
| * |
| * @type {Number} |
| */ |
| this.bytesPerSample = template.bytesPerSample; |
| |
| /** |
| * The number of audio channels (ie: 1 for mono, 2 for stereo). |
| * |
| * @type {Number} |
| */ |
| this.channels = template.channels; |
| |
| /** |
| * The number of samples per second, per channel. |
| * |
| * @type {Number} |
| */ |
| this.rate = template.rate; |
| |
| }; |
| |
| /** |
| * Parses the given mimetype, returning a new Guacamole.RawAudioFormat |
| * which describes the type of raw audio data represented by that mimetype. If |
| * the mimetype is not a supported raw audio data mimetype, null is returned. |
| * |
| * @param {String} mimetype |
| * The audio mimetype to parse. |
| * |
| * @returns {Guacamole.RawAudioFormat} |
| * A new Guacamole.RawAudioFormat which describes the type of raw |
| * audio data represented by the given mimetype, or null if the given |
| * mimetype is not supported. |
| */ |
| Guacamole.RawAudioFormat.parse = function parseFormat(mimetype) { |
| |
| var bytesPerSample; |
| |
| // Rate is absolutely required - if null is still present later, the |
| // mimetype must not be supported |
| var rate = null; |
| |
| // Default for both "audio/L8" and "audio/L16" is one channel |
| var channels = 1; |
| |
| // "audio/L8" has one byte per sample |
| if (mimetype.substring(0, 9) === 'audio/L8;') { |
| mimetype = mimetype.substring(9); |
| bytesPerSample = 1; |
| } |
| |
| // "audio/L16" has two bytes per sample |
| else if (mimetype.substring(0, 10) === 'audio/L16;') { |
| mimetype = mimetype.substring(10); |
| bytesPerSample = 2; |
| } |
| |
| // All other types are unsupported |
| else |
| return null; |
| |
| // Parse all parameters |
| var parameters = mimetype.split(','); |
| for (var i = 0; i < parameters.length; i++) { |
| |
| var parameter = parameters[i]; |
| |
| // All parameters must have an equals sign separating name from value |
| var equals = parameter.indexOf('='); |
| if (equals === -1) |
| return null; |
| |
| // Parse name and value from parameter string |
| var name = parameter.substring(0, equals); |
| var value = parameter.substring(equals+1); |
| |
| // Handle each supported parameter |
| switch (name) { |
| |
| // Number of audio channels |
| case 'channels': |
| channels = parseInt(value); |
| break; |
| |
| // Sample rate |
| case 'rate': |
| rate = parseInt(value); |
| break; |
| |
| // All other parameters are unsupported |
| default: |
| return null; |
| |
| } |
| |
| }; |
| |
| // The rate parameter is required |
| if (rate === null) |
| return null; |
| |
| // Return parsed format details |
| return new Guacamole.RawAudioFormat({ |
| bytesPerSample : bytesPerSample, |
| channels : channels, |
| rate : rate |
| }); |
| |
| }; |