RecordRTC.js

'use strict';

// Last time updated: 2017-08-12 5:10:02 AM UTC

// ________________
// RecordRTC v5.4.3

// Open-Sourced: https://github.com/muaz-khan/RecordRTC

// --------------------------------------------------
// Muaz Khan     - www.MuazKhan.com
// MIT License   - www.WebRTC-Experiment.com/licence
// --------------------------------------------------

// ____________
// RecordRTC.js

/**
 * {@link https://github.com/muaz-khan/RecordRTC|RecordRTC} is a WebRTC JavaScript library for audio/video as well as screen activity recording. It supports Chrome, Firefox, Opera, Android, and Microsoft Edge. Platforms: Linux, Mac and Windows. 
 * @summary Record audio, video or screen inside the browser.
 * @license {@link https://github.com/muaz-khan/RecordRTC#license|MIT}
 * @author {@link http://www.MuazKhan.com|Muaz Khan}
 * @typedef RecordRTC
 * @class
 * @example
 * var recorder = RecordRTC(mediaStream or [arrayOfMediaStream], {
 *     type: 'video', // audio or video or gif or canvas
 *     recorderType: MediaStreamRecorder || CanvasRecorder || StereoAudioRecorder || Etc
 * });
 * recorder.startRecording();
 * @see For further information:
 * @see {@link https://github.com/muaz-khan/RecordRTC|RecordRTC Source Code}
 * @param {MediaStream} mediaStream - Single media-stream object, array of media-streams, html-canvas-element, etc.
 * @param {object} config - {type:"video", recorderType: MediaStreamRecorder, disableLogs: true, numberOfAudioChannels: 1, bufferSize: 0, sampleRate: 0, desiredSampRate: 16000, video: HTMLVideoElement, etc.}
 */

function RecordRTC(mediaStream, config) {
    if (!mediaStream) {
        throw 'First parameter is required.';
    }

    config = config || {
        type: 'video'
    };

    config = new RecordRTCConfiguration(mediaStream, config);

    // a reference to user's recordRTC object
    var self = this;

    function startRecording() {
        if (!config.disableLogs) {
            console.log('started recording ' + config.type + ' stream.');
        }

        if (mediaRecorder) {
            mediaRecorder.clearRecordedData();
            mediaRecorder.record();

            setState('recording');

            if (self.recordingDuration) {
                handleRecordingDuration();
            }
            return self;
        }

        initRecorder(function() {
            if (self.recordingDuration) {
                handleRecordingDuration();
            }
        });

        return self;
    }

    function initRecorder(initCallback) {
        if (initCallback) {
            config.initCallback = function() {
                initCallback();
                initCallback = config.initCallback = null; // recorder.initRecorder should be call-backed once.
            };
        }

        var Recorder = new GetRecorderType(mediaStream, config);

        mediaRecorder = new Recorder(mediaStream, config);
        mediaRecorder.record();

        setState('recording');

        if (!config.disableLogs) {
            console.log('Initialized recorderType:', mediaRecorder.constructor.name, 'for output-type:', config.type);
        }
    }

    function stopRecording(callback) {
        if (!mediaRecorder) {
            return console.warn(WARNING);
        }

        if (self.state === 'paused') {
            self.resumeRecording();

            setTimeout(function() {
                stopRecording(callback);
            }, 1);
            return;
        }

        if (self.state !== 'recording') {
            if (!config.disableLogs) {
                console.warn('Unable to stop the recording. Recording state: ', self.state);
            }
            return;
        }

        if (!config.disableLogs) {
            console.warn('Stopped recording ' + config.type + ' stream.');
        }

        if (config.type !== 'gif') {
            mediaRecorder.stop(_callback);
        } else {
            mediaRecorder.stop();
            _callback();
        }

        setState('stopped');

        function _callback(__blob) {
            Object.keys(mediaRecorder).forEach(function(key) {
                if (typeof mediaRecorder[key] === 'function') {
                    return;
                }

                self[key] = mediaRecorder[key];
            });

            var blob = mediaRecorder.blob;

            if (!blob) {
                if (__blob) {
                    mediaRecorder.blob = blob = __blob;
                } else {
                    throw 'Recording failed.';
                }
            }

            if (callback) {
                var url = URL.createObjectURL(blob);

                if (typeof callback.call === 'function') {
                    callback.call(self, url);
                } else {
                    callback(url);
                }
            }

            if (blob && !config.disableLogs) {
                console.log(blob.type, '->', bytesToSize(blob.size));
            }

            if (!config.autoWriteToDisk) {
                return;
            }

            getDataURL(function(dataURL) {
                var parameter = {};
                parameter[config.type + 'Blob'] = dataURL;
                DiskStorage.Store(parameter);
            });
        }
    }

    function pauseRecording() {
        if (!mediaRecorder) {
            return console.warn(WARNING);
        }

        if (self.state !== 'recording') {
            if (!config.disableLogs) {
                console.warn('Unable to pause the recording. Recording state: ', self.state);
            }
            return;
        }

        setState('paused');

        mediaRecorder.pause();

        if (!config.disableLogs) {
            console.log('Paused recording.');
        }
    }

    function resumeRecording() {
        if (!mediaRecorder) {
            return console.warn(WARNING);
        }

        if (self.state !== 'paused') {
            if (!config.disableLogs) {
                console.warn('Unable to resume the recording. Recording state: ', self.state);
            }
            return;
        }

        setState('recording');

        // not all libs have this method yet
        mediaRecorder.resume();

        if (!config.disableLogs) {
            console.log('Resumed recording.');
        }
    }

    function readFile(_blob) {
        postMessage(new FileReaderSync().readAsDataURL(_blob));
    }

    function getDataURL(callback, _mediaRecorder) {
        if (!callback) {
            throw 'Pass a callback function over getDataURL.';
        }

        var blob = _mediaRecorder ? _mediaRecorder.blob : (mediaRecorder || {}).blob;

        if (!blob) {
            if (!config.disableLogs) {
                console.warn('Blob encoder did not finish its job yet.');
            }

            setTimeout(function() {
                getDataURL(callback, _mediaRecorder);
            }, 1000);
            return;
        }

        if (typeof Worker !== 'undefined' && !navigator.mozGetUserMedia) {
            var webWorker = processInWebWorker(readFile);

            webWorker.onmessage = function(event) {
                callback(event.data);
            };

            webWorker.postMessage(blob);
        } else {
            var reader = new FileReader();
            reader.readAsDataURL(blob);
            reader.onload = function(event) {
                callback(event.target.result);
            };
        }

        function processInWebWorker(_function) {
            var blob = URL.createObjectURL(new Blob([_function.toString(),
                'this.onmessage =  function (e) {' + _function.name + '(e.data);}'
            ], {
                type: 'application/javascript'
            }));

            var worker = new Worker(blob);
            URL.revokeObjectURL(blob);
            return worker;
        }
    }

    function handleRecordingDuration(counter) {
        counter = counter || 0;

        if (self.state === 'paused') {
            setTimeout(function() {
                handleRecordingDuration(counter);
            }, 1000);
            return;
        }

        if (self.state === 'stopped') {
            return;
        }

        if (counter >= self.recordingDuration) {
            stopRecording(self.onRecordingStopped);
            return;
        }

        counter += 1000; // 1-second

        setTimeout(function() {
            handleRecordingDuration(counter);
        }, 1000);
    }

    function setState(state) {
        self.state = state;

        if (typeof self.onStateChanged.call === 'function') {
            self.onStateChanged.call(self, state);
        } else {
            self.onStateChanged(state);
        }
    }

    var WARNING = 'It seems that "startRecording" is not invoked for ' + config.type + ' recorder.';

    var mediaRecorder;

    var returnObject = {
        /**
         * This method starts the recording.
         * @method
         * @memberof RecordRTC
         * @instance
         * @example
         * var recorder = RecordRTC(mediaStream, {
         *     type: 'video'
         * });
         * recorder.startRecording();
         */
        startRecording: startRecording,

        /**
         * This method stops the recording. It is strongly recommended to get "blob" or "URI" inside the callback to make sure all recorders finished their job.
         * @param {function} callback - Callback to get the recorded blob.
         * @method
         * @memberof RecordRTC
         * @instance
         * @example
         * recorder.stopRecording(function() {
         *     // use either "this" or "recorder" object; both are identical
         *     video.src = this.toURL();
         *     var blob = this.getBlob();
         * });
         */
        stopRecording: stopRecording,

        /**
         * This method pauses the recording. You can resume recording using "resumeRecording" method.
         * @method
         * @memberof RecordRTC
         * @instance
         * @todo Firefox is unable to pause the recording. Fix it.
         * @example
         * recorder.pauseRecording();  // pause the recording
         * recorder.resumeRecording(); // resume again
         */
        pauseRecording: pauseRecording,

        /**
         * This method resumes the recording.
         * @method
         * @memberof RecordRTC
         * @instance
         * @example
         * recorder.pauseRecording();  // first of all, pause the recording
         * recorder.resumeRecording(); // now resume it
         */
        resumeRecording: resumeRecording,

        /**
         * This method initializes the recording.
         * @method
         * @memberof RecordRTC
         * @instance
         * @todo This method should be deprecated.
         * @example
         * recorder.initRecorder();
         */
        initRecorder: initRecorder,

        /**
         * Ask RecordRTC to auto-stop the recording after 5 minutes.
         * @method
         * @memberof RecordRTC
         * @instance
         * @example
         * var fiveMinutes = 5 * 1000 * 60;
         * recorder.setRecordingDuration(fiveMinutes, function() {
         *    var blob = this.getBlob();
         *    video.src = this.toURL();
         * });
         * 
         * // or otherwise
         * recorder.setRecordingDuration(fiveMinutes).onRecordingStopped(function() {
         *    var blob = this.getBlob();
         *    video.src = this.toURL();
         * });
         */
        setRecordingDuration: function(recordingDuration, callback) {
            if (typeof recordingDuration === 'undefined') {
                throw 'recordingDuration is required.';
            }

            if (typeof recordingDuration !== 'number') {
                throw 'recordingDuration must be a number.';
            }

            self.recordingDuration = recordingDuration;
            self.onRecordingStopped = callback || function() {};

            return {
                onRecordingStopped: function(callback) {
                    self.onRecordingStopped = callback;
                }
            };
        },

        /**
         * This method can be used to clear/reset all the recorded data.
         * @method
         * @memberof RecordRTC
         * @instance
         * @todo Figure out the difference between "reset" and "clearRecordedData" methods.
         * @example
         * recorder.clearRecordedData();
         */
        clearRecordedData: function() {
            if (!mediaRecorder) {
                return console.warn(WARNING);
            }

            mediaRecorder.clearRecordedData();

            if (!config.disableLogs) {
                console.log('Cleared old recorded data.');
            }
        },

        /**
         * Get the recorded blob. Use this method inside the "stopRecording" callback.
         * @method
         * @memberof RecordRTC
         * @instance
         * @example
         * recorder.stopRecording(function() {
         *     var blob = this.getBlob();
         *
         *     var file = new File([blob], 'filename.webm', {
         *         type: 'video/webm'
         *     });
         *
         *     var formData = new FormData();
         *     formData.append('file', file); // upload "File" object rather than a "Blob"
         *     uploadToServer(formData);
         * });
         * @returns {Blob} Returns recorded data as "Blob" object.
         */
        getBlob: function() {
            if (!mediaRecorder) {
                return console.warn(WARNING);
            }

            return mediaRecorder.blob;
        },

        /**
         * Get data-URI instead of Blob.
         * @param {function} callback - Callback to get the Data-URI.
         * @method
         * @memberof RecordRTC
         * @instance
         * @example
         * recorder.stopRecording(function() {
         *     recorder.getDataURL(function(dataURI) {
         *         video.src = dataURI;
         *     });
         * });
         */
        getDataURL: getDataURL,

        /**
         * Get virtual/temporary URL. Usage of this URL is limited to current tab.
         * @method
         * @memberof RecordRTC
         * @instance
         * @example
         * recorder.stopRecording(function() {
         *     video.src = this.toURL();
         * });
         * @returns {String} Returns a virtual/temporary URL for the recorded "Blob".
         */
        toURL: function() {
            if (!mediaRecorder) {
                return console.warn(WARNING);
            }

            return URL.createObjectURL(mediaRecorder.blob);
        },

        /**
         * Get internal recording object (i.e. internal module) e.g. MutliStreamRecorder, MediaStreamRecorder, StereoAudioRecorder or WhammyRecorder etc.
         * @method
         * @memberof RecordRTC
         * @instance
         * @example
         * var internal = recorder.getInternalRecorder();
         * if(internal instanceof MultiStreamRecorder) {
         *     internal.addStreams([newAudioStream]);
         *     internal.resetVideoStreams([screenStream]);
         * }
         * @returns {Object} Returns internal recording object.
         */
        getInternalRecorder: function() {
            return mediaRecorder;
        },

        /**
         * Invoke save-as dialog to save the recorded blob into your disk.
         * @param {string} fileName - Set your own file name.
         * @method
         * @memberof RecordRTC
         * @instance
         * @example
         * recorder.stopRecording(function() {
         *     this.save('file-name');
         *
         *     // or manually:
         *     invokeSaveAsDialog(this.getBlob(), 'filename.webm');
         * });
         */
        save: function(fileName) {
            if (!mediaRecorder) {
                return console.warn(WARNING);
            }

            invokeSaveAsDialog(mediaRecorder.blob, fileName);
        },

        /**
         * This method gets a blob from indexed-DB storage.
         * @param {function} callback - Callback to get the recorded blob.
         * @method
         * @memberof RecordRTC
         * @instance
         * @example
         * recorder.getFromDisk(function(dataURL) {
         *     video.src = dataURL;
         * });
         */
        getFromDisk: function(callback) {
            if (!mediaRecorder) {
                return console.warn(WARNING);
            }

            RecordRTC.getFromDisk(config.type, callback);
        },

        /**
         * This method appends an array of webp images to the recorded video-blob. It takes an "array" object.
         * @type {Array.<Array>}
         * @param {Array} arrayOfWebPImages - Array of webp images.
         * @method
         * @memberof RecordRTC
         * @instance
         * @todo This method should be deprecated.
         * @example
         * var arrayOfWebPImages = [];
         * arrayOfWebPImages.push({
         *     duration: index,
         *     image: 'data:image/webp;base64,...'
         * });
         * recorder.setAdvertisementArray(arrayOfWebPImages);
         */
        setAdvertisementArray: function(arrayOfWebPImages) {
            config.advertisement = [];

            var length = arrayOfWebPImages.length;
            for (var i = 0; i < length; i++) {
                config.advertisement.push({
                    duration: i,
                    image: arrayOfWebPImages[i]
                });
            }
        },

        /**
         * It is equivalent to <code class="str">"recorder.getBlob()"</code> method. Usage of "getBlob" is recommended, though.
         * @property {Blob} blob - Recorded Blob can be accessed using this property.
         * @memberof RecordRTC
         * @instance
         * @readonly
         * @example
         * recorder.stopRecording(function() {
         *     var blob = this.blob;
         *
         *     // below one is recommended
         *     var blob = this.getBlob();
         * });
         */
        blob: null,

        /**
         * This works only with {recorderType:StereoAudioRecorder}. Use this property on "stopRecording" to verify the encoder's sample-rates.
         * @property {number} bufferSize - Buffer-size used to encode the WAV container
         * @memberof RecordRTC
         * @instance
         * @readonly
         * @example
         * recorder.stopRecording(function() {
         *     alert('Recorder used this buffer-size: ' + this.bufferSize);
         * });
         */
        bufferSize: 0,

        /**
         * This works only with {recorderType:StereoAudioRecorder}. Use this property on "stopRecording" to verify the encoder's sample-rates.
         * @property {number} sampleRate - Sample-rates used to encode the WAV container
         * @memberof RecordRTC
         * @instance
         * @readonly
         * @example
         * recorder.stopRecording(function() {
         *     alert('Recorder used these sample-rates: ' + this.sampleRate);
         * });
         */
        sampleRate: 0,

        /**
         * {recorderType:StereoAudioRecorder} returns ArrayBuffer object.
         * @property {ArrayBuffer} buffer - Audio ArrayBuffer, supported only in Chrome.
         * @memberof RecordRTC
         * @instance
         * @readonly
         * @example
         * recorder.stopRecording(function() {
         *     var arrayBuffer = this.buffer;
         *     alert(arrayBuffer.byteLength);
         * });
         */
        buffer: null,

        /**
         * This method resets the recorder. So that you can reuse single recorder instance many times.
         * @method
         * @memberof RecordRTC
         * @instance
         * @example
         * recorder.reset();
         * recorder.startRecording();
         */
        reset: function() {
            if (mediaRecorder && typeof mediaRecorder.clearRecordedData === 'function') {
                mediaRecorder.clearRecordedData();
            }
            mediaRecorder = null;
            setState('inactive');
            self.blob = null;
        },

        /**
         * This method is called whenever recorder's state changes. Use this as an "event".
         * @property {String} state - A recorder's state can be: recording, paused, stopped or inactive.
         * @method
         * @memberof RecordRTC
         * @instance
         * @example
         * recorder.onStateChanged = function(state) {
         *     console.log('Recorder state: ', state);
         * };
         */
        onStateChanged: function(state) {
            if (!config.disableLogs) {
                console.log('Recorder state changed:', state);
            }
        },

        /**
         * A recorder can have inactive, recording, paused or stopped states.
         * @property {String} state - A recorder's state can be: recording, paused, stopped or inactive.
         * @memberof RecordRTC
         * @static
         * @readonly
         * @example
         * // this looper function will keep you updated about the recorder's states.
         * (function looper() {
         *     document.querySelector('h1').innerHTML = 'Recorder's state is: ' + recorder.state;
         *     if(recorder.state === 'stopped') return; // ignore+stop
         *     setTimeout(looper, 1000); // update after every 3-seconds
         * })();
         * recorder.startRecording();
         */
        state: 'inactive',

        /**
         * Get recorder's readonly state.
         * @method
         * @memberof RecordRTC
         * @example
         * var state = recorder.getState();
         * @returns {String} Returns recording state.
         */
        getState: function() {
            return self.state;
        }
    };

    if (!this) {
        self = returnObject;
        return returnObject;
    }

    // if someone wants to use RecordRTC with the "new" keyword.
    for (var prop in returnObject) {
        this[prop] = returnObject[prop];
    }

    self = this;

    return returnObject;
}

/**
 * This method can be used to get all recorded blobs from IndexedDB storage.
 * @param {string} type - 'all' or 'audio' or 'video' or 'gif'
 * @param {function} callback - Callback function to get all stored blobs.
 * @method
 * @memberof RecordRTC
 * @example
 * RecordRTC.getFromDisk('all', function(dataURL, type){
 *     if(type === 'audio') { }
 *     if(type === 'video') { }
 *     if(type === 'gif')   { }
 * });
 */
RecordRTC.getFromDisk = function(type, callback) {
    if (!callback) {
        throw 'callback is mandatory.';
    }

    console.log('Getting recorded ' + (type === 'all' ? 'blobs' : type + ' blob ') + ' from disk!');
    DiskStorage.Fetch(function(dataURL, _type) {
        if (type !== 'all' && _type === type + 'Blob' && callback) {
            callback(dataURL);
        }

        if (type === 'all' && callback) {
            callback(dataURL, _type.replace('Blob', ''));
        }
    });
};

/**
 * This method can be used to store recorded blobs into IndexedDB storage.
 * @param {object} options - {audio: Blob, video: Blob, gif: Blob}
 * @method
 * @memberof RecordRTC
 * @example
 * RecordRTC.writeToDisk({
 *     audio: audioBlob,
 *     video: videoBlob,
 *     gif  : gifBlob
 * });
 */
RecordRTC.writeToDisk = function(options) {
    console.log('Writing recorded blob(s) to disk!');
    options = options || {};
    if (options.audio && options.video && options.gif) {
        options.audio.getDataURL(function(audioDataURL) {
            options.video.getDataURL(function(videoDataURL) {
                options.gif.getDataURL(function(gifDataURL) {
                    DiskStorage.Store({
                        audioBlob: audioDataURL,
                        videoBlob: videoDataURL,
                        gifBlob: gifDataURL
                    });
                });
            });
        });
    } else if (options.audio && options.video) {
        options.audio.getDataURL(function(audioDataURL) {
            options.video.getDataURL(function(videoDataURL) {
                DiskStorage.Store({
                    audioBlob: audioDataURL,
                    videoBlob: videoDataURL
                });
            });
        });
    } else if (options.audio && options.gif) {
        options.audio.getDataURL(function(audioDataURL) {
            options.gif.getDataURL(function(gifDataURL) {
                DiskStorage.Store({
                    audioBlob: audioDataURL,
                    gifBlob: gifDataURL
                });
            });
        });
    } else if (options.video && options.gif) {
        options.video.getDataURL(function(videoDataURL) {
            options.gif.getDataURL(function(gifDataURL) {
                DiskStorage.Store({
                    videoBlob: videoDataURL,
                    gifBlob: gifDataURL
                });
            });
        });
    } else if (options.audio) {
        options.audio.getDataURL(function(audioDataURL) {
            DiskStorage.Store({
                audioBlob: audioDataURL
            });
        });
    } else if (options.video) {
        options.video.getDataURL(function(videoDataURL) {
            DiskStorage.Store({
                videoBlob: videoDataURL
            });
        });
    } else if (options.gif) {
        options.gif.getDataURL(function(gifDataURL) {
            DiskStorage.Store({
                gifBlob: gifDataURL
            });
        });
    }
};

if (typeof module !== 'undefined' /* && !!module.exports*/ ) {
    module.exports = RecordRTC;
}

if (typeof define === 'function' && define.amd) {
    define('RecordRTC', [], function() {
        return RecordRTC;
    });
}

// __________________________
// RecordRTC-Configuration.js

/**
 * {@link RecordRTCConfiguration} is an inner/private helper for {@link RecordRTC}.
 * @summary It configures the 2nd parameter passed over {@link RecordRTC} and returns a valid "config" object.
 * @license {@link https://github.com/muaz-khan/RecordRTC#license|MIT}
 * @author {@link http://www.MuazKhan.com|Muaz Khan}
 * @typedef RecordRTCConfiguration
 * @class
 * @example
 * var options = RecordRTCConfiguration(mediaStream, options);
 * @see {@link https://github.com/muaz-khan/RecordRTC|RecordRTC Source Code}
 * @param {MediaStream} mediaStream - MediaStream object fetched using getUserMedia API or generated using captureStreamUntilEnded or WebAudio API.
 * @param {object} config - {type:"video", disableLogs: true, numberOfAudioChannels: 1, bufferSize: 0, sampleRate: 0, video: HTMLVideoElement, getNativeBlob:true, etc.}
 */

function RecordRTCConfiguration(mediaStream, config) {
    if (config.recorderType && !config.type) {
        if (config.recorderType === WhammyRecorder || config.recorderType === CanvasRecorder) {
            config.type = 'video';
        } else if (config.recorderType === GifRecorder) {
            config.type = 'gif';
        } else if (config.recorderType === StereoAudioRecorder) {
            config.type = 'audio';
        } else if (config.recorderType === MediaStreamRecorder) {
            if (mediaStream.getAudioTracks().length && mediaStream.getVideoTracks().length) {
                config.type = 'video';
            } else if (mediaStream.getAudioTracks().length && !mediaStream.getVideoTracks().length) {
                config.type = 'audio';
            } else if (!mediaStream.getAudioTracks().length && mediaStream.getVideoTracks().length) {
                config.type = 'audio';
            } else {
                // config.type = 'UnKnown';
            }
        }
    }

    if (typeof MediaStreamRecorder !== 'undefined' && typeof MediaRecorder !== 'undefined' && 'requestData' in MediaRecorder.prototype) {
        if (!config.mimeType) {
            config.mimeType = 'video/webm';
        }

        if (!config.type) {
            config.type = config.mimeType.split('/')[0];
        }

        if (!config.bitsPerSecond) {
            // config.bitsPerSecond = 128000;
        }
    }

    // consider default type=audio
    if (!config.type) {
        if (config.mimeType) {
            config.type = config.mimeType.split('/')[0];
        }
        if (!config.type) {
            config.type = 'audio';
        }
    }

    return config;
}

// __________________
// GetRecorderType.js

/**
 * {@link GetRecorderType} is an inner/private helper for {@link RecordRTC}.
 * @summary It returns best recorder-type available for your browser.
 * @license {@link https://github.com/muaz-khan/RecordRTC#license|MIT}
 * @author {@link http://www.MuazKhan.com|Muaz Khan}
 * @typedef GetRecorderType
 * @class
 * @example
 * var RecorderType = GetRecorderType(options);
 * var recorder = new RecorderType(options);
 * @see {@link https://github.com/muaz-khan/RecordRTC|RecordRTC Source Code}
 * @param {MediaStream} mediaStream - MediaStream object fetched using getUserMedia API or generated using captureStreamUntilEnded or WebAudio API.
 * @param {object} config - {type:"video", disableLogs: true, numberOfAudioChannels: 1, bufferSize: 0, sampleRate: 0, video: HTMLVideoElement, etc.}
 */

function GetRecorderType(mediaStream, config) {
    var recorder;

    // StereoAudioRecorder can work with all three: Edge, Firefox and Chrome
    // todo: detect if it is Edge, then auto use: StereoAudioRecorder
    if (isChrome || isEdge || isOpera) {
        // Media Stream Recording API has not been implemented in chrome yet;
        // That's why using WebAudio API to record stereo audio in WAV format
        recorder = StereoAudioRecorder;
    }

    if (typeof MediaRecorder !== 'undefined' && 'requestData' in MediaRecorder.prototype && !isChrome) {
        recorder = MediaStreamRecorder;
    }

    // video recorder (in WebM format)
    if (config.type === 'video' && (isChrome || isOpera)) {
        recorder = WhammyRecorder;
    }

    // video recorder (in Gif format)
    if (config.type === 'gif') {
        recorder = GifRecorder;
    }

    // html2canvas recording!
    if (config.type === 'canvas') {
        recorder = CanvasRecorder;
    }

    if (isMediaRecorderCompatible() && recorder !== CanvasRecorder && recorder !== GifRecorder && typeof MediaRecorder !== 'undefined' && 'requestData' in MediaRecorder.prototype) {
        if ((mediaStream.getVideoTracks && mediaStream.getVideoTracks().length) || (mediaStream.getAudioTracks && mediaStream.getAudioTracks().length)) {
            // audio-only recording
            if (config.type === 'audio') {
                if (typeof MediaRecorder.isTypeSupported === 'function' && MediaRecorder.isTypeSupported('audio/webm')) {
                    recorder = MediaStreamRecorder;
                }
                // else recorder = StereoAudioRecorder;
            } else {
                // video or screen tracks
                if (typeof MediaRecorder.isTypeSupported === 'function' && MediaRecorder.isTypeSupported('video/webm')) {
                    recorder = MediaStreamRecorder;
                }
            }
        }
    }

    if (config.recorderType) {
        recorder = config.recorderType;
    }

    if (mediaStream instanceof Array && mediaStream.length) {
        recorder = MultiStreamRecorder;
    }

    if (!config.disableLogs && !!recorder && !!recorder.name) {
        console.log('Using recorderType:', recorder.name || recorder.constructor.name);
    }

    return recorder;
}

// _____________
// MRecordRTC.js

/**
 * MRecordRTC runs on top of {@link RecordRTC} to bring multiple recordings in a single place, by providing simple API.
 * @summary MRecordRTC stands for "Multiple-RecordRTC".
 * @license {@link https://github.com/muaz-khan/RecordRTC#license|MIT}
 * @author {@link http://www.MuazKhan.com|Muaz Khan}
 * @typedef MRecordRTC
 * @class
 * @example
 * var recorder = new MRecordRTC();
 * recorder.addStream(MediaStream);
 * recorder.mediaType = {
 *     audio: true, // or StereoAudioRecorder or MediaStreamRecorder
 *     video: true, // or WhammyRecorder or MediaStreamRecorder
 *     gif: true    // or GifRecorder
 * };
 * // mimeType is optional and should be set only in advance cases.
 * recorder.mimeType = {
 *     audio: 'audio/wav',
 *     video: 'video/webm',
 *     gif:   'image/gif'
 * };
 * recorder.startRecording();
 * @see For further information:
 * @see {@link https://github.com/muaz-khan/RecordRTC/tree/master/MRecordRTC|MRecordRTC Source Code}
 * @param {MediaStream} mediaStream - MediaStream object fetched using getUserMedia API or generated using captureStreamUntilEnded or WebAudio API.
 * @requires {@link RecordRTC}
 */

function MRecordRTC(mediaStream) {

    /**
     * This method attaches MediaStream object to {@link MRecordRTC}.
     * @param {MediaStream} mediaStream - A MediaStream object, either fetched using getUserMedia API, or generated using captureStreamUntilEnded or WebAudio API.
     * @method
     * @memberof MRecordRTC
     * @example
     * recorder.addStream(MediaStream);
     */
    this.addStream = function(_mediaStream) {
        if (_mediaStream) {
            mediaStream = _mediaStream;
        }
    };

    /**
     * This property can be used to set the recording type e.g. audio, or video, or gif, or canvas.
     * @property {object} mediaType - {audio: true, video: true, gif: true}
     * @memberof MRecordRTC
     * @example
     * var recorder = new MRecordRTC();
     * recorder.mediaType = {
     *     audio: true, // TRUE or StereoAudioRecorder or MediaStreamRecorder
     *     video: true, // TRUE or WhammyRecorder or MediaStreamRecorder
     *     gif  : true  // TRUE or GifRecorder
     * };
     */
    this.mediaType = {
        audio: true,
        video: true
    };

    /**
     * This method starts recording.
     * @method
     * @memberof MRecordRTC
     * @example
     * recorder.startRecording();
     */
    this.startRecording = function() {
        var mediaType = this.mediaType;
        var recorderType;
        var mimeType = this.mimeType || {
            audio: null,
            video: null,
            gif: null
        };

        if (typeof mediaType.audio !== 'function' && isMediaRecorderCompatible() && mediaStream.getAudioTracks && !mediaStream.getAudioTracks().length) {
            mediaType.audio = false;
        }

        if (typeof mediaType.video !== 'function' && isMediaRecorderCompatible() && mediaStream.getVideoTracks && !mediaStream.getVideoTracks().length) {
            mediaType.video = false;
        }

        if (typeof mediaType.gif !== 'function' && isMediaRecorderCompatible() && mediaStream.getVideoTracks && !mediaStream.getVideoTracks().length) {
            mediaType.gif = false;
        }

        if (!mediaType.audio && !mediaType.video && !mediaType.gif) {
            throw 'MediaStream must have either audio or video tracks.';
        }

        if (!!mediaType.audio) {
            recorderType = null;
            if (typeof mediaType.audio === 'function') {
                recorderType = mediaType.audio;
            }

            this.audioRecorder = new RecordRTC(mediaStream, {
                type: 'audio',
                bufferSize: this.bufferSize,
                sampleRate: this.sampleRate,
                numberOfAudioChannels: this.numberOfAudioChannels || 2,
                disableLogs: this.disableLogs,
                recorderType: recorderType,
                mimeType: mimeType.audio,
                timeSlice: this.timeSlice,
                onTimeStamp: this.onTimeStamp
            });

            if (!mediaType.video) {
                this.audioRecorder.startRecording();
            }
        }

        if (!!mediaType.video) {
            recorderType = null;
            if (typeof mediaType.video === 'function') {
                recorderType = mediaType.video;
            }

            var newStream = mediaStream;

            if (isMediaRecorderCompatible() && !!mediaType.audio && typeof mediaType.audio === 'function') {
                var videoTrack = mediaStream.getVideoTracks()[0];

                if (!!navigator.mozGetUserMedia) {
                    newStream = new MediaStream();
                    newStream.addTrack(videoTrack);

                    if (recorderType && recorderType === WhammyRecorder) {
                        // Firefox does NOT support webp-encoding yet
                        recorderType = MediaStreamRecorder;
                    }
                } else {
                    newStream = new MediaStream([videoTrack]);
                }
            }

            this.videoRecorder = new RecordRTC(newStream, {
                type: 'video',
                video: this.video,
                canvas: this.canvas,
                frameInterval: this.frameInterval || 10,
                disableLogs: this.disableLogs,
                recorderType: recorderType,
                mimeType: mimeType.video,
                timeSlice: this.timeSlice,
                onTimeStamp: this.onTimeStamp
            });

            if (!mediaType.audio) {
                this.videoRecorder.startRecording();
            }
        }

        if (!!mediaType.audio && !!mediaType.video) {
            var self = this;

            // this line prevents StereoAudioRecorder
            // todo: fix it
            if (isMediaRecorderCompatible() /* && !this.audioRecorder */ ) {
                self.audioRecorder = null;
                self.videoRecorder.startRecording();
            } else {
                self.videoRecorder.initRecorder(function() {
                    self.audioRecorder.initRecorder(function() {
                        // Both recorders are ready to record things accurately
                        self.videoRecorder.startRecording();
                        self.audioRecorder.startRecording();
                    });
                });
            }
        }

        if (!!mediaType.gif) {
            recorderType = null;
            if (typeof mediaType.gif === 'function') {
                recorderType = mediaType.gif;
            }
            this.gifRecorder = new RecordRTC(mediaStream, {
                type: 'gif',
                frameRate: this.frameRate || 200,
                quality: this.quality || 10,
                disableLogs: this.disableLogs,
                recorderType: recorderType,
                mimeType: mimeType.gif
            });
            this.gifRecorder.startRecording();
        }
    };

    /**
     * This method stops recording.
     * @param {function} callback - Callback function is invoked when all encoders finished their jobs.
     * @method
     * @memberof MRecordRTC
     * @example
     * recorder.stopRecording(function(recording){
     *     var audioBlob = recording.audio;
     *     var videoBlob = recording.video;
     *     var gifBlob   = recording.gif;
     * });
     */
    this.stopRecording = function(callback) {
        callback = callback || function() {};

        if (this.audioRecorder) {
            this.audioRecorder.stopRecording(function(blobURL) {
                callback(blobURL, 'audio');
            });
        }

        if (this.videoRecorder) {
            this.videoRecorder.stopRecording(function(blobURL) {
                callback(blobURL, 'video');
            });
        }

        if (this.gifRecorder) {
            this.gifRecorder.stopRecording(function(blobURL) {
                callback(blobURL, 'gif');
            });
        }
    };

    /**
     * This method pauses recording.
     * @method
     * @memberof MRecordRTC
     * @example
     * recorder.pauseRecording();
     */
    this.pauseRecording = function() {
        if (this.audioRecorder) {
            this.audioRecorder.pauseRecording();
        }

        if (this.videoRecorder) {
            this.videoRecorder.pauseRecording();
        }

        if (this.gifRecorder) {
            this.gifRecorder.pauseRecording();
        }
    };

    /**
     * This method resumes recording.
     * @method
     * @memberof MRecordRTC
     * @example
     * recorder.resumeRecording();
     */
    this.resumeRecording = function() {
        if (this.audioRecorder) {
            this.audioRecorder.resumeRecording();
        }

        if (this.videoRecorder) {
            this.videoRecorder.resumeRecording();
        }

        if (this.gifRecorder) {
            this.gifRecorder.resumeRecording();
        }
    };

    /**
     * This method can be used to manually get all recorded blobs.
     * @param {function} callback - All recorded blobs are passed back to the "callback" function.
     * @method
     * @memberof MRecordRTC
     * @example
     * recorder.getBlob(function(recording){
     *     var audioBlob = recording.audio;
     *     var videoBlob = recording.video;
     *     var gifBlob   = recording.gif;
     * });
     * // or
     * var audioBlob = recorder.getBlob().audio;
     * var videoBlob = recorder.getBlob().video;
     */
    this.getBlob = function(callback) {
        var output = {};

        if (this.audioRecorder) {
            output.audio = this.audioRecorder.getBlob();
        }

        if (this.videoRecorder) {
            output.video = this.videoRecorder.getBlob();
        }

        if (this.gifRecorder) {
            output.gif = this.gifRecorder.getBlob();
        }

        if (callback) {
            callback(output);
        }

        return output;
    };

    /**
     * This method can be used to manually get all recorded blobs' DataURLs.
     * @param {function} callback - All recorded blobs' DataURLs are passed back to the "callback" function.
     * @method
     * @memberof MRecordRTC
     * @example
     * recorder.getDataURL(function(recording){
     *     var audioDataURL = recording.audio;
     *     var videoDataURL = recording.video;
     *     var gifDataURL   = recording.gif;
     * });
     */
    this.getDataURL = function(callback) {
        this.getBlob(function(blob) {
            if (blob.audio && blob.video) {
                getDataURL(blob.audio, function(_audioDataURL) {
                    getDataURL(blob.video, function(_videoDataURL) {
                        callback({
                            audio: _audioDataURL,
                            video: _videoDataURL
                        });
                    });
                });
            } else if (blob.audio) {
                getDataURL(blob.audio, function(_audioDataURL) {
                    callback({
                        audio: _audioDataURL
                    });
                });
            } else if (blob.video) {
                getDataURL(blob.video, function(_videoDataURL) {
                    callback({
                        video: _videoDataURL
                    });
                });
            }
        });

        function getDataURL(blob, callback00) {
            if (typeof Worker !== 'undefined') {
                var webWorker = processInWebWorker(function readFile(_blob) {
                    postMessage(new FileReaderSync().readAsDataURL(_blob));
                });

                webWorker.onmessage = function(event) {
                    callback00(event.data);
                };

                webWorker.postMessage(blob);
            } else {
                var reader = new FileReader();
                reader.readAsDataURL(blob);
                reader.onload = function(event) {
                    callback00(event.target.result);
                };
            }
        }

        function processInWebWorker(_function) {
            var blob = URL.createObjectURL(new Blob([_function.toString(),
                'this.onmessage =  function (e) {' + _function.name + '(e.data);}'
            ], {
                type: 'application/javascript'
            }));

            var worker = new Worker(blob);
            var url;
            if (typeof URL !== 'undefined') {
                url = URL;
            } else if (typeof webkitURL !== 'undefined') {
                url = webkitURL;
            } else {
                throw 'Neither URL nor webkitURL detected.';
            }
            url.revokeObjectURL(blob);
            return worker;
        }
    };

    /**
     * This method can be used to ask {@link MRecordRTC} to write all recorded blobs into IndexedDB storage.
     * @method
     * @memberof MRecordRTC
     * @example
     * recorder.writeToDisk();
     */
    this.writeToDisk = function() {
        RecordRTC.writeToDisk({
            audio: this.audioRecorder,
            video: this.videoRecorder,
            gif: this.gifRecorder
        });
    };

    /**
     * This method can be used to invoke a save-as dialog for all recorded blobs.
     * @param {object} args - {audio: 'audio-name', video: 'video-name', gif: 'gif-name'}
     * @method
     * @memberof MRecordRTC
     * @example
     * recorder.save({
     *     audio: 'audio-file-name',
     *     video: 'video-file-name',
     *     gif  : 'gif-file-name'
     * });
     */
    this.save = function(args) {
        args = args || {
            audio: true,
            video: true,
            gif: true
        };

        if (!!args.audio && this.audioRecorder) {
            this.audioRecorder.save(typeof args.audio === 'string' ? args.audio : '');
        }

        if (!!args.video && this.videoRecorder) {
            this.videoRecorder.save(typeof args.video === 'string' ? args.video : '');
        }
        if (!!args.gif && this.gifRecorder) {
            this.gifRecorder.save(typeof args.gif === 'string' ? args.gif : '');
        }
    };
}

/**
 * This method can be used to get all recorded blobs from IndexedDB storage.
 * @param {string} type - 'all' or 'audio' or 'video' or 'gif'
 * @param {function} callback - Callback function to get all stored blobs.
 * @method
 * @memberof MRecordRTC
 * @example
 * MRecordRTC.getFromDisk('all', function(dataURL, type){
 *     if(type === 'audio') { }
 *     if(type === 'video') { }
 *     if(type === 'gif')   { }
 * });
 */
MRecordRTC.getFromDisk = RecordRTC.getFromDisk;

/**
 * This method can be used to store recorded blobs into IndexedDB storage.
 * @param {object} options - {audio: Blob, video: Blob, gif: Blob}
 * @method
 * @memberof MRecordRTC
 * @example
 * MRecordRTC.writeToDisk({
 *     audio: audioBlob,
 *     video: videoBlob,
 *     gif  : gifBlob
 * });
 */
MRecordRTC.writeToDisk = RecordRTC.writeToDisk;

if (typeof RecordRTC !== 'undefined') {
    RecordRTC.MRecordRTC = MRecordRTC;
}

var browserFakeUserAgent = 'Fake/5.0 (FakeOS) AppleWebKit/123 (KHTML, like Gecko) Fake/12.3.4567.89 Fake/123.45';

(function(that) {
    if (!that) {
        return;
    }

    if (typeof window !== 'undefined') {
        return;
    }

    if (typeof global === 'undefined') {
        return;
    }

    global.navigator = {
        userAgent: browserFakeUserAgent,
        getUserMedia: function() {}
    };

    if (!global.console) {
        global.console = {};
    }

    if (typeof global.console.log === 'undefined' || typeof global.console.error === 'undefined') {
        global.console.error = global.console.log = global.console.log || function() {
            console.log(arguments);
        };
    }

    if (typeof document === 'undefined') {
        /*global document:true */
        that.document = {};

        document.createElement = document.captureStream = document.mozCaptureStream = function() {
            var obj = {
                getContext: function() {
                    return obj;
                },
                play: function() {},
                pause: function() {},
                drawImage: function() {},
                toDataURL: function() {
                    return '';
                }
            };
            return obj;
        };

        that.HTMLVideoElement = function() {};
    }

    if (typeof location === 'undefined') {
        /*global location:true */
        that.location = {
            protocol: 'file:',
            href: '',
            hash: ''
        };
    }

    if (typeof screen === 'undefined') {
        /*global screen:true */
        that.screen = {
            width: 0,
            height: 0
        };
    }

    if (typeof URL === 'undefined') {
        /*global screen:true */
        that.URL = {
            createObjectURL: function() {
                return '';
            },
            revokeObjectURL: function() {
                return '';
            }
        };
    }

    /*global window:true */
    that.window = global;
})(typeof global !== 'undefined' ? global : null);

// _____________________________
// Cross-Browser-Declarations.js

// animation-frame used in WebM recording

/*jshint -W079 */
var requestAnimationFrame = window.requestAnimationFrame;
if (typeof requestAnimationFrame === 'undefined') {
    if (typeof webkitRequestAnimationFrame !== 'undefined') {
        /*global requestAnimationFrame:true */
        requestAnimationFrame = webkitRequestAnimationFrame;
    } else if (typeof mozRequestAnimationFrame !== 'undefined') {
        /*global requestAnimationFrame:true */
        requestAnimationFrame = mozRequestAnimationFrame;
    } else if (typeof msRequestAnimationFrame !== 'undefined') {
        /*global requestAnimationFrame:true */
        requestAnimationFrame = msRequestAnimationFrame;
    } else if (typeof requestAnimationFrame === 'undefined') {
        // via: https://gist.github.com/paulirish/1579671
        var lastTime = 0;

        /*global requestAnimationFrame:true */
        requestAnimationFrame = function(callback, element) {
            var currTime = new Date().getTime();
            var timeToCall = Math.max(0, 16 - (currTime - lastTime));
            var id = setTimeout(function() {
                callback(currTime + timeToCall);
            }, timeToCall);
            lastTime = currTime + timeToCall;
            return id;
        };
    }
}

/*jshint -W079 */
var cancelAnimationFrame = window.cancelAnimationFrame;
if (typeof cancelAnimationFrame === 'undefined') {
    if (typeof webkitCancelAnimationFrame !== 'undefined') {
        /*global cancelAnimationFrame:true */
        cancelAnimationFrame = webkitCancelAnimationFrame;
    } else if (typeof mozCancelAnimationFrame !== 'undefined') {
        /*global cancelAnimationFrame:true */
        cancelAnimationFrame = mozCancelAnimationFrame;
    } else if (typeof msCancelAnimationFrame !== 'undefined') {
        /*global cancelAnimationFrame:true */
        cancelAnimationFrame = msCancelAnimationFrame;
    } else if (typeof cancelAnimationFrame === 'undefined') {
        /*global cancelAnimationFrame:true */
        cancelAnimationFrame = function(id) {
            clearTimeout(id);
        };
    }
}

// WebAudio API representer
var AudioContext = window.AudioContext;

if (typeof AudioContext === 'undefined') {
    if (typeof webkitAudioContext !== 'undefined') {
        /*global AudioContext:true */
        AudioContext = webkitAudioContext;
    }

    if (typeof mozAudioContext !== 'undefined') {
        /*global AudioContext:true */
        AudioContext = mozAudioContext;
    }
}

/*jshint -W079 */
var URL = window.URL;

if (typeof URL === 'undefined' && typeof webkitURL !== 'undefined') {
    /*global URL:true */
    URL = webkitURL;
}

if (typeof navigator !== 'undefined' && typeof navigator.getUserMedia === 'undefined') { // maybe window.navigator?
    if (typeof navigator.webkitGetUserMedia !== 'undefined') {
        navigator.getUserMedia = navigator.webkitGetUserMedia;
    }

    if (typeof navigator.mozGetUserMedia !== 'undefined') {
        navigator.getUserMedia = navigator.mozGetUserMedia;
    }
}

var isEdge = navigator.userAgent.indexOf('Edge') !== -1 && (!!navigator.msSaveBlob || !!navigator.msSaveOrOpenBlob);
var isOpera = !!window.opera || navigator.userAgent.indexOf('OPR/') !== -1;
var isChrome = !isOpera && !isEdge && !!navigator.webkitGetUserMedia;

var MediaStream = window.MediaStream;

if (typeof MediaStream === 'undefined' && typeof webkitMediaStream !== 'undefined') {
    MediaStream = webkitMediaStream;
}

/*global MediaStream:true */
if (typeof MediaStream !== 'undefined') {
    if (!('getVideoTracks' in MediaStream.prototype)) {
        MediaStream.prototype.getVideoTracks = function() {
            if (!this.getTracks) {
                return [];
            }

            var tracks = [];
            this.getTracks().forEach(function(track) {
                if (track.kind.toString().indexOf('video') !== -1) {
                    tracks.push(track);
                }
            });
            return tracks;
        };

        MediaStream.prototype.getAudioTracks = function() {
            if (!this.getTracks) {
                return [];
            }

            var tracks = [];
            this.getTracks().forEach(function(track) {
                if (track.kind.toString().indexOf('audio') !== -1) {
                    tracks.push(track);
                }
            });
            return tracks;
        };
    }

    // override "stop" method for all browsers
    MediaStream.prototype.__stop = MediaStream.prototype.stop;
    MediaStream.prototype.stop = function() {
        this.getAudioTracks().forEach(function(track) {
            if (!!track.stop) {
                track.stop();
            }
        });

        this.getVideoTracks().forEach(function(track) {
            if (!!track.stop) {
                track.stop();
            }
        });

        if (typeof this.__stop === 'function') {
            this.__stop();
        }
    };
}

// below function via: http://goo.gl/B3ae8c
/**
 * @param {number} bytes - Pass bytes and get formafted string.
 * @returns {string} - formafted string
 * @example
 * bytesToSize(1024*1024*5) === '5 GB'
 * @see {@link https://github.com/muaz-khan/RecordRTC|RecordRTC Source Code}
 */
function bytesToSize(bytes) {
    var k = 1000;
    var sizes = ['Bytes', 'KB', 'MB', 'GB', 'TB'];
    if (bytes === 0) {
        return '0 Bytes';
    }
    var i = parseInt(Math.floor(Math.log(bytes) / Math.log(k)), 10);
    return (bytes / Math.pow(k, i)).toPrecision(3) + ' ' + sizes[i];
}

/**
 * @param {Blob} file - File or Blob object. This parameter is required.
 * @param {string} fileName - Optional file name e.g. "Recorded-Video.webm"
 * @example
 * invokeSaveAsDialog(blob or file, [optional] fileName);
 * @see {@link https://github.com/muaz-khan/RecordRTC|RecordRTC Source Code}
 */
function invokeSaveAsDialog(file, fileName) {
    if (!file) {
        throw 'Blob object is required.';
    }

    if (!file.type) {
        try {
            file.type = 'video/webm';
        } catch (e) {}
    }

    var fileExtension = (file.type || 'video/webm').split('/')[1];

    if (fileName && fileName.indexOf('.') !== -1) {
        var splitted = fileName.split('.');
        fileName = splitted[0];
        fileExtension = splitted[1];
    }

    var fileFullName = (fileName || (Math.round(Math.random() * 9999999999) + 888888888)) + '.' + fileExtension;

    if (typeof navigator.msSaveOrOpenBlob !== 'undefined') {
        return navigator.msSaveOrOpenBlob(file, fileFullName);
    } else if (typeof navigator.msSaveBlob !== 'undefined') {
        return navigator.msSaveBlob(file, fileFullName);
    }

    var hyperlink = document.createElement('a');
    hyperlink.href = URL.createObjectURL(file);
    hyperlink.download = fileFullName;

    hyperlink.style = 'display:none;opacity:0;color:transparent;';
    (document.body || document.documentElement).appendChild(hyperlink);

    if (typeof hyperlink.click === 'function') {
        hyperlink.click();
    } else {
        hyperlink.target = '_blank';
        hyperlink.dispatchEvent(new MouseEvent('click', {
            view: window,
            bubbles: true,
            cancelable: true
        }));
    }

    URL.revokeObjectURL(hyperlink.href);
}

// __________ (used to handle stuff like http://goo.gl/xmE5eg) issue #129
// Storage.js

/**
 * Storage is a standalone object used by {@link RecordRTC} to store reusable objects e.g. "new AudioContext".
 * @license {@link https://github.com/muaz-khan/RecordRTC#license|MIT}
 * @author {@link http://www.MuazKhan.com|Muaz Khan}
 * @example
 * Storage.AudioContext === webkitAudioContext
 * @property {webkitAudioContext} AudioContext - Keeps a reference to AudioContext object.
 * @see {@link https://github.com/muaz-khan/RecordRTC|RecordRTC Source Code}
 */

var Storage = {};

if (typeof AudioContext !== 'undefined') {
    Storage.AudioContext = AudioContext;
} else if (typeof webkitAudioContext !== 'undefined') {
    Storage.AudioContext = webkitAudioContext;
}

if (typeof RecordRTC !== 'undefined') {
    RecordRTC.Storage = Storage;
}

function isMediaRecorderCompatible() {
    var isOpera = !!window.opera || navigator.userAgent.indexOf(' OPR/') >= 0;
    var isChrome = !!window.chrome && !isOpera;
    var isFirefox = typeof window.InstallTrigger !== 'undefined';

    if (isFirefox) {
        return true;
    }

    var nVer = navigator.appVersion;
    var nAgt = navigator.userAgent;
    var fullVersion = '' + parseFloat(navigator.appVersion);
    var majorVersion = parseInt(navigator.appVersion, 10);
    var nameOffset, verOffset, ix;

    if (isChrome || isOpera) {
        verOffset = nAgt.indexOf('Chrome');
        fullVersion = nAgt.substring(verOffset + 7);
    }

    // trim the fullVersion string at semicolon/space if present
    if ((ix = fullVersion.indexOf(';')) !== -1) {
        fullVersion = fullVersion.substring(0, ix);
    }

    if ((ix = fullVersion.indexOf(' ')) !== -1) {
        fullVersion = fullVersion.substring(0, ix);
    }

    majorVersion = parseInt('' + fullVersion, 10);

    if (isNaN(majorVersion)) {
        fullVersion = '' + parseFloat(navigator.appVersion);
        majorVersion = parseInt(navigator.appVersion, 10);
    }

    return majorVersion >= 49;
}

// ______________________
// MediaStreamRecorder.js

/**
 * MediaStreamRecorder is an abstraction layer for {@link https://w3c.github.io/mediacapture-record/MediaRecorder.html|MediaRecorder API}. It is used by {@link RecordRTC} to record MediaStream(s) in both Chrome and Firefox.
 * @summary Runs top over {@link https://w3c.github.io/mediacapture-record/MediaRecorder.html|MediaRecorder API}.
 * @license {@link https://github.com/muaz-khan/RecordRTC#license|MIT}
 * @author {@link https://github.com/muaz-khan|Muaz Khan}
 * @typedef MediaStreamRecorder
 * @class
 * @example
 * var config = {
 *     mimeType: 'video/webm', // vp8, vp9, h264, mkv, opus/vorbis
 *     audioBitsPerSecond : 256 * 8 * 1024,
 *     videoBitsPerSecond : 256 * 8 * 1024,
 *     bitsPerSecond: 256 * 8 * 1024,  // if this is provided, skip above two
 *     checkForInactiveTracks: true,
 *     timeSlice: 1000, // concatenate intervals based blobs
 *     ignoreMutedMedia: true
 * }
 * var recorder = new MediaStreamRecorder(mediaStream, config);
 * recorder.record();
 * recorder.stop(function(blob) {
 *     video.src = URL.createObjectURL(blob);
 *
 *     // or
 *     var blob = recorder.blob;
 * });
 * @see {@link https://github.com/muaz-khan/RecordRTC|RecordRTC Source Code}
 * @param {MediaStream} mediaStream - MediaStream object fetched using getUserMedia API or generated using captureStreamUntilEnded or WebAudio API.
 * @param {object} config - {disableLogs:true, initCallback: function, mimeType: "video/webm", timeSlice: 1000}
 * @throws Will throw an error if first argument "MediaStream" is missing. Also throws error if "MediaRecorder API" are not supported by the browser.
 */

function MediaStreamRecorder(mediaStream, config) {
    var self = this;

    if (typeof mediaStream === 'undefined') {
        throw 'First argument "MediaStream" is required.';
    }

    if (typeof MediaRecorder === 'undefined') {
        throw 'Your browser does not supports Media Recorder API. Please try other modules e.g. WhammyRecorder or StereoAudioRecorder.';
    }

    config = config || {
        // bitsPerSecond: 256 * 8 * 1024,
        mimeType: 'video/webm'
    };

    if (config.type === 'audio') {
        if (mediaStream.getVideoTracks().length && mediaStream.getAudioTracks().length) {
            var stream;
            if (!!navigator.mozGetUserMedia) {
                stream = new MediaStream();
                stream.addTrack(mediaStream.getAudioTracks()[0]);
            } else {
                // webkitMediaStream
                stream = new MediaStream(mediaStream.getAudioTracks());
            }
            mediaStream = stream;
        }

        if (!config.mimeType || config.mimeType.toString().toLowerCase().indexOf('audio') === -1) {
            config.mimeType = isChrome ? 'audio/webm' : 'audio/ogg';
        }

        if (config.mimeType && config.mimeType.toString().toLowerCase() !== 'audio/ogg' && !!navigator.mozGetUserMedia) {
            // forcing better codecs on Firefox (via #166)
            config.mimeType = 'audio/ogg';
        }
    }

    var arrayOfBlobs = [];

    /**
     * This method returns array of blobs. Use only with "timeSlice". Its useful to preview recording anytime, without using the "stop" method.
     * @method
     * @memberof MediaStreamRecorder
     * @example
     * var arrayOfBlobs = recorder.getArrayOfBlobs();
     * @returns {Array} Returns array of recorded blobs.
     */
    this.getArrayOfBlobs = function() {
        return arrayOfBlobs;
    };

    /**
     * This method records MediaStream.
     * @method
     * @memberof MediaStreamRecorder
     * @example
     * recorder.record();
     */
    this.record = function() {
        // set defaults
        self.blob = null;
        self.clearRecordedData();
        self.timestamps = [];
        allStates = [];
        arrayOfBlobs = [];

        var recorderHints = config;

        if (!config.disableLogs) {
            console.log('Passing following config over MediaRecorder API.', recorderHints);
        }

        if (mediaRecorder) {
            // mandatory to make sure Firefox doesn't fails to record streams 3-4 times without reloading the page.
            mediaRecorder = null;
        }

        if (isChrome && !isMediaRecorderCompatible()) {
            // to support video-only recording on stable
            recorderHints = 'video/vp8';
        }

        if (typeof MediaRecorder.isTypeSupported === 'function' && recorderHints.mimeType) {
            if (!MediaRecorder.isTypeSupported(recorderHints.mimeType)) {
                if (!config.disableLogs) {
                    console.warn('MediaRecorder API seems unable to record mimeType:', recorderHints.mimeType);
                }

                recorderHints.mimeType = config.type === 'audio' ? 'audio/webm' : 'video/webm';
            }
        }

        // using MediaRecorder API here
        try {
            mediaRecorder = new MediaRecorder(mediaStream, recorderHints);

            // reset
            config.mimeType = recorderHints.mimeType;
        } catch (e) {
            // chrome-based fallback
            mediaRecorder = new MediaRecorder(mediaStream);
        }

        // old hack?
        if (recorderHints.mimeType && !MediaRecorder.isTypeSupported && 'canRecordMimeType' in mediaRecorder && mediaRecorder.canRecordMimeType(recorderHints.mimeType) === false) {
            if (!config.disableLogs) {
                console.warn('MediaRecorder API seems unable to record mimeType:', recorderHints.mimeType);
            }
        }

        // ignore muted/disabled/inactive tracks
        mediaRecorder.ignoreMutedMedia = config.ignoreMutedMedia === true;

        // Dispatching OnDataAvailable Handler
        mediaRecorder.ondataavailable = function(e) {
            if (e.data) {
                allStates.push('ondataavailable: ' + bytesToSize(e.data.size));
            }

            if (typeof config.timeSlice === 'number') {
                if (e.data && e.data.size && e.data.size > 100) {
                    arrayOfBlobs.push(e.data);
                    updateTimeStamp();
                }
                return;
            }

            if (!e.data || !e.data.size || e.data.size < 100 || self.blob) {
                // make sure that stopRecording always getting fired
                // even if there is invalid data
                if (self.recordingCallback) {
                    self.recordingCallback(new Blob([], {
                        type: mediaRecorder.mimeType || recorderHints.mimeType || 'video/webm'
                    }));
                    self.recordingCallback = null;
                }
                return;
            }

            self.blob = config.getNativeBlob ? e.data : new Blob([e.data], {
                type: mediaRecorder.mimeType || recorderHints.mimeType || 'video/webm'
            });

            if (self.recordingCallback) {
                self.recordingCallback(self.blob);
                self.recordingCallback = null;
            }
        };

        mediaRecorder.onstart = function() {
            allStates.push('started');
        };

        mediaRecorder.onpause = function() {
            allStates.push('paused');
        };

        mediaRecorder.onresume = function() {
            allStates.push('resumed');
        };

        mediaRecorder.onstop = function() {
            allStates.push('stopped');
        };

        mediaRecorder.onerror = function(error) {
            allStates.push('error: ' + error);

            if (!config.disableLogs) {
                // via: https://w3c.github.io/mediacapture-record/MediaRecorder.html#exception-summary
                if (error.name.toString().toLowerCase().indexOf('invalidstate') !== -1) {
                    console.error('The MediaRecorder is not in a state in which the proposed operation is allowed to be executed.', error);
                } else if (error.name.toString().toLowerCase().indexOf('notsupported') !== -1) {
                    console.error('MIME type (', recorderHints.mimeType, ') is not supported.', error);
                } else if (error.name.toString().toLowerCase().indexOf('security') !== -1) {
                    console.error('MediaRecorder security error', error);
                }

                // older code below
                else if (error.name === 'OutOfMemory') {
                    console.error('The UA has exhaused the available memory. User agents SHOULD provide as much additional information as possible in the message attribute.', error);
                } else if (error.name === 'IllegalStreamModification') {
                    console.error('A modification to the stream has occurred that makes it impossible to continue recording. An example would be the addition of a Track while recording is occurring. User agents SHOULD provide as much additional information as possible in the message attribute.', error);
                } else if (error.name === 'OtherRecordingError') {
                    console.error('Used for an fatal error other than those listed above. User agents SHOULD provide as much additional information as possible in the message attribute.', error);
                } else if (error.name === 'GenericError') {
                    console.error('The UA cannot provide the codec or recording option that has been requested.', error);
                } else {
                    console.error('MediaRecorder Error', error);
                }
            }

            (function(looper) {
                if (!self.manuallyStopped && mediaRecorder && mediaRecorder.state === 'inactive') {
                    delete config.timeslice;

                    // 10 minutes, enough?
                    mediaRecorder.start(10 * 60 * 1000);
                    return;
                }

                setTimeout(looper, 1000);
            })();

            if (mediaRecorder.state !== 'inactive' && mediaRecorder.state !== 'stopped') {
                mediaRecorder.stop();
            }
        };

        if (typeof config.timeSlice === 'number') {
            updateTimeStamp();
            mediaRecorder.start(config.timeSlice);
        } else {
            // default is 60 minutes; enough?
            // use config => {timeSlice: 1000} otherwise

            mediaRecorder.start(3.6e+6);
        }

        if (config.initCallback) {
            config.initCallback(); // old code
        }
    };

    /**
     * @property {Array} timestamps - Array of time stamps
     * @memberof MediaStreamRecorder
     * @example
     * console.log(recorder.timestamps);
     */
    this.timestamps = [];

    function updateTimeStamp() {
        self.timestamps.push(new Date().getTime());

        if (typeof config.onTimeStamp === 'function') {
            config.onTimeStamp(self.timestamps[self.timestamps.length - 1], self.timestamps);
        }
    }

    /**
     * This method stops recording MediaStream.
     * @param {function} callback - Callback function, that is used to pass recorded blob back to the callee.
     * @method
     * @memberof MediaStreamRecorder
     * @example
     * recorder.stop(function(blob) {
     *     video.src = URL.createObjectURL(blob);
     * });
     */
    this.stop = function(callback) {
        self.manuallyStopped = true; // used inside the mediaRecorder.onerror

        if (!mediaRecorder) {
            return;
        }

        this.recordingCallback = function(blob) {
            if (callback) {
                callback(blob);
            }
        };

        if (mediaRecorder.state === 'recording') {
            mediaRecorder.stop();
        }

        if (typeof config.timeSlice === 'number') {
            setTimeout(function() {
                self.blob = new Blob(arrayOfBlobs, {
                    type: mediaRecorder.mimeType || config.mimeType || 'video/webm'
                });

                self.recordingCallback(self.blob);
            }, 100);
        }
    };

    /**
     * This method pauses the recording process.
     * @method
     * @memberof MediaStreamRecorder
     * @example
     * recorder.pause();
     */
    this.pause = function() {
        if (!mediaRecorder) {
            return;
        }

        if (mediaRecorder.state === 'recording') {
            mediaRecorder.pause();
        }
    };

    /**
     * This method resumes the recording process.
     * @method
     * @memberof MediaStreamRecorder
     * @example
     * recorder.resume();
     */
    this.resume = function() {
        if (!mediaRecorder) {
            return;
        }

        if (mediaRecorder.state === 'paused') {
            mediaRecorder.resume();
        }
    };

    /**
     * This method resets currently recorded data.
     * @method
     * @memberof MediaStreamRecorder
     * @example
     * recorder.clearRecordedData();
     */
    this.clearRecordedData = function() {
        arrayOfBlobs = [];
        mediaRecorder = null;
        self.timestamps = [];
    };

    // Reference to "MediaRecorder" object
    var mediaRecorder;

    /**
     * Access to native MediaRecorder API
     * @method
     * @memberof MediaStreamRecorder
     * @instance
     * @example
     * var internal = recorder.getInternalRecorder();
     * internal.ondataavailable = function() {}; // override
     * internal.stream, internal.onpause, internal.onstop, etc.
     * @returns {Object} Returns internal recording object.
     */
    this.getInternalRecorder = function() {
        return mediaRecorder;
    };

    function isMediaStreamActive() {
        if ('active' in mediaStream) {
            if (!mediaStream.active) {
                return false;
            }
        } else if ('ended' in mediaStream) { // old hack
            if (mediaStream.ended) {
                return false;
            }
        }
        return true;
    }

    /**
     * @property {Blob} blob - Recorded data as "Blob" object.
     * @memberof MediaStreamRecorder
     * @example
     * recorder.stop(function() {
     *     var blob = recorder.blob;
     * });
     */
    this.blob = null;


    /**
     * Get MediaRecorder readonly state.
     * @method
     * @memberof MediaStreamRecorder
     * @example
     * var state = recorder.getState();
     * @returns {String} Returns recording state.
     */
    this.getState = function() {
        if (!mediaRecorder) {
            return 'inactive';
        }

        return mediaRecorder.state || 'inactive';
    };

    // list of all recording states
    var allStates = [];

    /**
     * Get MediaRecorder all recording states.
     * @method
     * @memberof MediaStreamRecorder
     * @example
     * var state = recorder.getAllStates();
     * @returns {Array} Returns all recording states
     */
    this.getAllStates = function() {
        return allStates;
    };

    // if any Track within the MediaStream is muted or not enabled at any time, 
    // the browser will only record black frames 
    // or silence since that is the content produced by the Track
    // so we need to stopRecording as soon as any single track ends.
    if (typeof config.checkForInactiveTracks === 'undefined') {
        config.checkForInactiveTracks = false; // disable to minimize CPU usage
    }

    var self = this;

    // this method checks if media stream is stopped
    // or if any track is ended.
    (function looper() {
        if (!mediaRecorder || config.checkForInactiveTracks === false) {
            return;
        }

        if (isMediaStreamActive() === false) {
            if (!config.disableLogs) {
                console.log('MediaStream seems stopped.');
            }
            self.stop();
            return;
        }

        setTimeout(looper, 1000); // check every second
    })();

    // for debugging
    this.name = 'MediaStreamRecorder';
    this.toString = function() {
        return this.name;
    };
}

if (typeof RecordRTC !== 'undefined') {
    RecordRTC.MediaStreamRecorder = MediaStreamRecorder;
}

// source code from: http://typedarray.org/wp-content/projects/WebAudioRecorder/script.js
// https://github.com/mattdiamond/Recorderjs#license-mit
// ______________________
// StereoAudioRecorder.js

/**
 * StereoAudioRecorder is a standalone class used by {@link RecordRTC} to bring "stereo" audio-recording in chrome.
 * @summary JavaScript standalone object for stereo audio recording.
 * @license {@link https://github.com/muaz-khan/RecordRTC#license|MIT}
 * @author {@link http://www.MuazKhan.com|Muaz Khan}
 * @typedef StereoAudioRecorder
 * @class
 * @example
 * var recorder = new StereoAudioRecorder(MediaStream, {
 *     sampleRate: 44100,
 *     bufferSize: 4096
 * });
 * recorder.record();
 * recorder.stop(function(blob) {
 *     video.src = URL.createObjectURL(blob);
 * });
 * @see {@link https://github.com/muaz-khan/RecordRTC|RecordRTC Source Code}
 * @param {MediaStream} mediaStream - MediaStream object fetched using getUserMedia API or generated using captureStreamUntilEnded or WebAudio API.
 * @param {object} config - {sampleRate: 44100, bufferSize: 4096, numberOfAudioChannels: 1, etc.}
 */

function StereoAudioRecorder(mediaStream, config) {
    if (!mediaStream.getAudioTracks().length) {
        throw 'Your stream has no audio tracks.';
    }

    config = config || {};

    var self = this;

    // variables
    var leftchannel = [];
    var rightchannel = [];
    var recording = false;
    var recordingLength = 0;
    var jsAudioNode;

    var numberOfAudioChannels = 2;

    /**
     * Set sample rates such as 8K or 16K. Reference: http://stackoverflow.com/a/28977136/552182
     * @property {number} desiredSampRate - Desired Bits per sample * 1000
     * @memberof StereoAudioRecorder
     * @instance
     * @example
     * var recorder = StereoAudioRecorder(mediaStream, {
     *   desiredSampRate: 16 * 1000 // bits-per-sample * 1000
     * });
     */
    var desiredSampRate = config.desiredSampRate;

    // backward compatibility
    if (config.leftChannel === true) {
        numberOfAudioChannels = 1;
    }

    if (config.numberOfAudioChannels === 1) {
        numberOfAudioChannels = 1;
    }

    if (!config.disableLogs) {
        console.log('StereoAudioRecorder is set to record number of channels: ', numberOfAudioChannels);
    }

    // if any Track within the MediaStream is muted or not enabled at any time, 
    // the browser will only record black frames 
    // or silence since that is the content produced by the Track
    // so we need to stopRecording as soon as any single track ends.
    if (typeof config.checkForInactiveTracks === 'undefined') {
        config.checkForInactiveTracks = true;
    }

    function isMediaStreamActive() {
        if (config.checkForInactiveTracks === false) {
            // always return "true"
            return true;
        }

        if ('active' in mediaStream) {
            if (!mediaStream.active) {
                return false;
            }
        } else if ('ended' in mediaStream) { // old hack
            if (mediaStream.ended) {
                return false;
            }
        }
        return true;
    }

    /**
     * This method records MediaStream.
     * @method
     * @memberof StereoAudioRecorder
     * @example
     * recorder.record();
     */
    this.record = function() {
        if (isMediaStreamActive() === false) {
            throw 'Please make sure MediaStream is active.';
        }

        // reset the buffers for the new recording
        leftchannel.length = rightchannel.length = 0;
        recordingLength = 0;

        if (audioInput) {
            audioInput.connect(jsAudioNode);
        }

        // to prevent self audio to be connected with speakers
        // jsAudioNode.connect(context.destination);

        isAudioProcessStarted = isPaused = false;
        recording = true;
    };

    function mergeLeftRightBuffers(config, callback) {
        function mergeAudioBuffers(config, cb) {
            var numberOfAudioChannels = config.numberOfAudioChannels;

            // todo: "slice(0)" --- is it causes loop? Should be removed?
            var leftBuffers = config.leftBuffers.slice(0);
            var rightBuffers = config.rightBuffers.slice(0);
            var sampleRate = config.sampleRate;
            var internalInterleavedLength = config.internalInterleavedLength;
            var desiredSampRate = config.desiredSampRate;

            if (numberOfAudioChannels === 2) {
                leftBuffers = mergeBuffers(leftBuffers, internalInterleavedLength);
                rightBuffers = mergeBuffers(rightBuffers, internalInterleavedLength);
                if (desiredSampRate) {
                    leftBuffers = interpolateArray(leftBuffers, desiredSampRate, sampleRate);
                    rightBuffers = interpolateArray(rightBuffers, desiredSampRate, sampleRate);
                }
            }

            if (numberOfAudioChannels === 1) {
                leftBuffers = mergeBuffers(leftBuffers, internalInterleavedLength);
                if (desiredSampRate) {
                    leftBuffers = interpolateArray(leftBuffers, desiredSampRate, sampleRate);
                }
            }

            // set sample rate as desired sample rate
            if (desiredSampRate) {
                sampleRate = desiredSampRate;
            }

            // for changing the sampling rate, reference:
            // http://stackoverflow.com/a/28977136/552182
            function interpolateArray(data, newSampleRate, oldSampleRate) {
                var fitCount = Math.round(data.length * (newSampleRate / oldSampleRate));
                //var newData = new Array();
                var newData = [];
                //var springFactor = new Number((data.length - 1) / (fitCount - 1));
                var springFactor = Number((data.length - 1) / (fitCount - 1));
                newData[0] = data[0]; // for new allocation
                for (var i = 1; i < fitCount - 1; i++) {
                    var tmp = i * springFactor;
                    //var before = new Number(Math.floor(tmp)).toFixed();
                    //var after = new Number(Math.ceil(tmp)).toFixed();
                    var before = Number(Math.floor(tmp)).toFixed();
                    var after = Number(Math.ceil(tmp)).toFixed();
                    var atPoint = tmp - before;
                    newData[i] = linearInterpolate(data[before], data[after], atPoint);
                }
                newData[fitCount - 1] = data[data.length - 1]; // for new allocation
                return newData;
            }

            function linearInterpolate(before, after, atPoint) {
                return before + (after - before) * atPoint;
            }

            function mergeBuffers(channelBuffer, rLength) {
                var result = new Float64Array(rLength);
                var offset = 0;
                var lng = channelBuffer.length;

                for (var i = 0; i < lng; i++) {
                    var buffer = channelBuffer[i];
                    result.set(buffer, offset);
                    offset += buffer.length;
                }

                return result;
            }

            function interleave(leftChannel, rightChannel) {
                var length = leftChannel.length + rightChannel.length;

                var result = new Float64Array(length);

                var inputIndex = 0;

                for (var index = 0; index < length;) {
                    result[index++] = leftChannel[inputIndex];
                    result[index++] = rightChannel[inputIndex];
                    inputIndex++;
                }
                return result;
            }

            function writeUTFBytes(view, offset, string) {
                var lng = string.length;
                for (var i = 0; i < lng; i++) {
                    view.setUint8(offset + i, string.charCodeAt(i));
                }
            }

            // interleave both channels together
            var interleaved;

            if (numberOfAudioChannels === 2) {
                interleaved = interleave(leftBuffers, rightBuffers);
            }

            if (numberOfAudioChannels === 1) {
                interleaved = leftBuffers;
            }

            var interleavedLength = interleaved.length;

            // create wav file
            var resultingBufferLength = 44 + interleavedLength * 2;

            var buffer = new ArrayBuffer(resultingBufferLength);

            var view = new DataView(buffer);

            // RIFF chunk descriptor/identifier 
            writeUTFBytes(view, 0, 'RIFF');

            // RIFF chunk length
            view.setUint32(4, 44 + interleavedLength * 2, true);

            // RIFF type 
            writeUTFBytes(view, 8, 'WAVE');

            // format chunk identifier 
            // FMT sub-chunk
            writeUTFBytes(view, 12, 'fmt ');

            // format chunk length 
            view.setUint32(16, 16, true);

            // sample format (raw)
            view.setUint16(20, 1, true);

            // stereo (2 channels)
            view.setUint16(22, numberOfAudioChannels, true);

            // sample rate 
            view.setUint32(24, sampleRate, true);

            // byte rate (sample rate * block align)
            view.setUint32(28, sampleRate * 2, true);

            // block align (channel count * bytes per sample) 
            view.setUint16(32, numberOfAudioChannels * 2, true);

            // bits per sample 
            view.setUint16(34, 16, true);

            // data sub-chunk
            // data chunk identifier 
            writeUTFBytes(view, 36, 'data');

            // data chunk length 
            view.setUint32(40, interleavedLength * 2, true);

            // write the PCM samples
            var lng = interleavedLength;
            var index = 44;
            var volume = 1;
            for (var i = 0; i < lng; i++) {
                view.setInt16(index, interleaved[i] * (0x7FFF * volume), true);
                index += 2;
            }

            if (cb) {
                return cb({
                    buffer: buffer,
                    view: view
                });
            }

            postMessage({
                buffer: buffer,
                view: view
            });
        }

        if (!isChrome) {
            // its Microsoft Edge
            mergeAudioBuffers(config, function(data) {
                callback(data.buffer, data.view);
            });
            return;
        }


        var webWorker = processInWebWorker(mergeAudioBuffers);

        webWorker.onmessage = function(event) {
            callback(event.data.buffer, event.data.view);

            // release memory
            URL.revokeObjectURL(webWorker.workerURL);
        };

        webWorker.postMessage(config);
    }

    function processInWebWorker(_function) {
        var workerURL = URL.createObjectURL(new Blob([_function.toString(),
            ';this.onmessage =  function (e) {' + _function.name + '(e.data);}'
        ], {
            type: 'application/javascript'
        }));

        var worker = new Worker(workerURL);
        worker.workerURL = workerURL;
        return worker;
    }

    /**
     * This method stops recording MediaStream.
     * @param {function} callback - Callback function, that is used to pass recorded blob back to the callee.
     * @method
     * @memberof StereoAudioRecorder
     * @example
     * recorder.stop(function(blob) {
     *     video.src = URL.createObjectURL(blob);
     * });
     */
    this.stop = function(callback) {
        // stop recording
        recording = false;

        // to make sure onaudioprocess stops firing
        // audioInput.disconnect();

        mergeLeftRightBuffers({
            desiredSampRate: desiredSampRate,
            sampleRate: sampleRate,
            numberOfAudioChannels: numberOfAudioChannels,
            internalInterleavedLength: recordingLength,
            leftBuffers: leftchannel,
            rightBuffers: numberOfAudioChannels === 1 ? [] : rightchannel
        }, function(buffer, view) {
            /**
             * @property {Blob} blob - The recorded blob object.
             * @memberof StereoAudioRecorder
             * @example
             * recorder.stop(function(){
             *     var blob = recorder.blob;
             * });
             */
            self.blob = new Blob([view], {
                type: 'audio/wav'
            });

            /**
             * @property {ArrayBuffer} buffer - The recorded buffer object.
             * @memberof StereoAudioRecorder
             * @example
             * recorder.stop(function(){
             *     var buffer = recorder.buffer;
             * });
             */
            self.buffer = new ArrayBuffer(view.buffer.byteLength);

            /**
             * @property {DataView} view - The recorded data-view object.
             * @memberof StereoAudioRecorder
             * @example
             * recorder.stop(function(){
             *     var view = recorder.view;
             * });
             */
            self.view = view;

            self.sampleRate = desiredSampRate || sampleRate;
            self.bufferSize = bufferSize;

            // recorded audio length
            self.length = recordingLength;

            if (callback) {
                callback(self.blob);
            }

            isAudioProcessStarted = false;
        });
    };

    if (!Storage.AudioContextConstructor) {
        Storage.AudioContextConstructor = new Storage.AudioContext();
    }

    var context = Storage.AudioContextConstructor;

    // creates an audio node from the microphone incoming stream
    var audioInput = context.createMediaStreamSource(mediaStream);

    var legalBufferValues = [0, 256, 512, 1024, 2048, 4096, 8192, 16384];

    /**
     * From the spec: This value controls how frequently the audioprocess event is
     * dispatched and how many sample-frames need to be processed each call.
     * Lower values for buffer size will result in a lower (better) latency.
     * Higher values will be necessary to avoid audio breakup and glitches
     * The size of the buffer (in sample-frames) which needs to
     * be processed each time onprocessaudio is called.
     * Legal values are (256, 512, 1024, 2048, 4096, 8192, 16384).
     * @property {number} bufferSize - Buffer-size for how frequently the audioprocess event is dispatched.
     * @memberof StereoAudioRecorder
     * @example
     * recorder = new StereoAudioRecorder(mediaStream, {
     *     bufferSize: 4096
     * });
     */

    // "0" means, let chrome decide the most accurate buffer-size for current platform.
    var bufferSize = typeof config.bufferSize === 'undefined' ? 4096 : config.bufferSize;

    if (legalBufferValues.indexOf(bufferSize) === -1) {
        if (!config.disableLogs) {
            console.warn('Legal values for buffer-size are ' + JSON.stringify(legalBufferValues, null, '\t'));
        }
    }

    if (context.createJavaScriptNode) {
        jsAudioNode = context.createJavaScriptNode(bufferSize, numberOfAudioChannels, numberOfAudioChannels);
    } else if (context.createScriptProcessor) {
        jsAudioNode = context.createScriptProcessor(bufferSize, numberOfAudioChannels, numberOfAudioChannels);
    } else {
        throw 'WebAudio API has no support on this browser.';
    }

    // connect the stream to the gain node
    audioInput.connect(jsAudioNode);

    if (!config.bufferSize) {
        bufferSize = jsAudioNode.bufferSize; // device buffer-size
    }

    /**
     * The sample rate (in sample-frames per second) at which the
     * AudioContext handles audio. It is assumed that all AudioNodes
     * in the context run at this rate. In making this assumption,
     * sample-rate converters or "varispeed" processors are not supported
     * in real-time processing.
     * The sampleRate parameter describes the sample-rate of the
     * linear PCM audio data in the buffer in sample-frames per second.
     * An implementation must support sample-rates in at least
     * the range 22050 to 96000.
     * @property {number} sampleRate - Buffer-size for how frequently the audioprocess event is dispatched.
     * @memberof StereoAudioRecorder
     * @example
     * recorder = new StereoAudioRecorder(mediaStream, {
     *     sampleRate: 44100
     * });
     */
    var sampleRate = typeof config.sampleRate !== 'undefined' ? config.sampleRate : context.sampleRate || 44100;

    if (sampleRate < 22050 || sampleRate > 96000) {
        // Ref: http://stackoverflow.com/a/26303918/552182
        if (!config.disableLogs) {
            console.warn('sample-rate must be under range 22050 and 96000.');
        }
    }

    if (!config.disableLogs) {
        console.log('sample-rate', sampleRate);
        console.log('buffer-size', bufferSize);

        if (config.desiredSampRate) {
            console.log('Desired sample-rate', config.desiredSampRate);
        }
    }

    var isPaused = false;
    /**
     * This method pauses the recording process.
     * @method
     * @memberof StereoAudioRecorder
     * @example
     * recorder.pause();
     */
    this.pause = function() {
        isPaused = true;
    };

    /**
     * This method resumes the recording process.
     * @method
     * @memberof StereoAudioRecorder
     * @example
     * recorder.resume();
     */
    this.resume = function() {
        if (isMediaStreamActive() === false) {
            throw 'Please make sure MediaStream is active.';
        }

        if (!recording) {
            if (!config.disableLogs) {
                console.log('Seems recording has been restarted.');
            }
            this.record();
            return;
        }

        isPaused = false;
    };

    /**
     * This method resets currently recorded data.
     * @method
     * @memberof StereoAudioRecorder
     * @example
     * recorder.clearRecordedData();
     */
    this.clearRecordedData = function() {
        this.pause();

        leftchannel.length = rightchannel.length = 0;
        recordingLength = 0;
    };

    // for debugging
    this.name = 'StereoAudioRecorder';
    this.toString = function() {
        return this.name;
    };

    var isAudioProcessStarted = false;

    function onAudioProcessDataAvailable(e) {
        if (isPaused) {
            return;
        }

        if (isMediaStreamActive() === false) {
            if (!config.disableLogs) {
                console.log('MediaStream seems stopped.');
            }
            jsAudioNode.disconnect();
            recording = false;
        }

        if (!recording) {
            audioInput.disconnect();
            return;
        }

        /**
         * This method is called on "onaudioprocess" event's first invocation.
         * @method {function} onAudioProcessStarted
         * @memberof StereoAudioRecorder
         * @example
         * recorder.onAudioProcessStarted: function() { };
         */
        if (!isAudioProcessStarted) {
            isAudioProcessStarted = true;
            if (config.onAudioProcessStarted) {
                config.onAudioProcessStarted();
            }

            if (config.initCallback) {
                config.initCallback();
            }
        }

        var left = e.inputBuffer.getChannelData(0);

        // we clone the samples
        leftchannel.push(new Float32Array(left));

        if (numberOfAudioChannels === 2) {
            var right = e.inputBuffer.getChannelData(1);
            rightchannel.push(new Float32Array(right));
        }

        recordingLength += bufferSize;

        // export raw PCM
        self.recordingLength = recordingLength;
    }

    jsAudioNode.onaudioprocess = onAudioProcessDataAvailable;

    // to prevent self audio to be connected with speakers
    jsAudioNode.connect(context.destination);

    // export raw PCM
    this.leftchannel = leftchannel;
    this.rightchannel = rightchannel;
    this.numberOfAudioChannels = numberOfAudioChannels;
    this.desiredSampRate = desiredSampRate;
    this.sampleRate = sampleRate;
}

if (typeof RecordRTC !== 'undefined') {
    RecordRTC.StereoAudioRecorder = StereoAudioRecorder;
}

// _________________
// CanvasRecorder.js

/**
 * CanvasRecorder is a standalone class used by {@link RecordRTC} to bring HTML5-Canvas recording into video WebM. It uses HTML2Canvas library and runs top over {@link Whammy}.
 * @summary HTML2Canvas recording into video WebM.
 * @license {@link https://github.com/muaz-khan/RecordRTC#license|MIT}
 * @author {@link http://www.MuazKhan.com|Muaz Khan}
 * @typedef CanvasRecorder
 * @class
 * @example
 * var recorder = new CanvasRecorder(htmlElement, { disableLogs: true });
 * recorder.record();
 * recorder.stop(function(blob) {
 *     video.src = URL.createObjectURL(blob);
 * });
 * @see {@link https://github.com/muaz-khan/RecordRTC|RecordRTC Source Code}
 * @param {HTMLElement} htmlElement - querySelector/getElementById/getElementsByTagName[0]/etc.
 * @param {object} config - {disableLogs:true, initCallback: function}
 */

function CanvasRecorder(htmlElement, config) {
    if (typeof html2canvas === 'undefined' && htmlElement.nodeName.toLowerCase() !== 'canvas') {
        throw 'Please link: https://cdn.webrtc-experiment.com/screenshot.js';
    }

    config = config || {};
    if (!config.frameInterval) {
        config.frameInterval = 10;
    }

    // via DetectRTC.js
    var isCanvasSupportsStreamCapturing = false;
    ['captureStream', 'mozCaptureStream', 'webkitCaptureStream'].forEach(function(item) {
        if (item in document.createElement('canvas')) {
            isCanvasSupportsStreamCapturing = true;
        }
    });

    var _isChrome = (!!window.webkitRTCPeerConnection || !!window.webkitGetUserMedia) && !!window.chrome;

    var chromeVersion = 50;
    var matchArray = navigator.userAgent.match(/Chrom(e|ium)\/([0-9]+)\./);
    if (_isChrome && matchArray && matchArray[2]) {
        chromeVersion = parseInt(matchArray[2], 10);
    }

    if (_isChrome && chromeVersion < 52) {
        isCanvasSupportsStreamCapturing = false;
    }

    var globalCanvas, mediaStreamRecorder;

    if (isCanvasSupportsStreamCapturing) {
        if (!config.disableLogs) {
            console.log('Your browser supports both MediRecorder API and canvas.captureStream!');
        }

        if (htmlElement instanceof HTMLCanvasElement) {
            globalCanvas = htmlElement;
        } else if (htmlElement instanceof CanvasRenderingContext2D) {
            globalCanvas = htmlElement.canvas;
        } else {
            throw 'Please pass either HTMLCanvasElement or CanvasRenderingContext2D.';
        }
    } else if (!!navigator.mozGetUserMedia) {
        if (!config.disableLogs) {
            console.error('Canvas recording is NOT supported in Firefox.');
        }
    }

    var isRecording;

    /**
     * This method records Canvas.
     * @method
     * @memberof CanvasRecorder
     * @example
     * recorder.record();
     */
    this.record = function() {
        isRecording = true;

        if (isCanvasSupportsStreamCapturing) {
            // CanvasCaptureMediaStream
            var canvasMediaStream;
            if ('captureStream' in globalCanvas) {
                canvasMediaStream = globalCanvas.captureStream(25); // 25 FPS
            } else if ('mozCaptureStream' in globalCanvas) {
                canvasMediaStream = globalCanvas.mozCaptureStream(25);
            } else if ('webkitCaptureStream' in globalCanvas) {
                canvasMediaStream = globalCanvas.webkitCaptureStream(25);
            }

            try {
                var mdStream = new MediaStream();
                mdStream.addTrack(canvasMediaStream.getVideoTracks()[0]);
                canvasMediaStream = mdStream;
            } catch (e) {}

            if (!canvasMediaStream) {
                throw 'captureStream API are NOT available.';
            }

            // Note: Jan 18, 2016 status is that, 
            // Firefox MediaRecorder API can't record CanvasCaptureMediaStream object.
            mediaStreamRecorder = new MediaStreamRecorder(canvasMediaStream, {
                mimeType: 'video/webm'
            });
            mediaStreamRecorder.record();
        } else {
            whammy.frames = [];
            lastTime = new Date().getTime();
            drawCanvasFrame();
        }

        if (config.initCallback) {
            config.initCallback();
        }
    };

    this.getWebPImages = function(callback) {
        if (htmlElement.nodeName.toLowerCase() !== 'canvas') {
            callback();
            return;
        }

        var framesLength = whammy.frames.length;
        whammy.frames.forEach(function(frame, idx) {
            var framesRemaining = framesLength - idx;
            if (!config.disableLogs) {
                console.log(framesRemaining + '/' + framesLength + ' frames remaining');
            }

            if (config.onEncodingCallback) {
                config.onEncodingCallback(framesRemaining, framesLength);
            }

            var webp = frame.image.toDataURL('image/webp', 1);
            whammy.frames[idx].image = webp;
        });

        if (!config.disableLogs) {
            console.log('Generating WebM');
        }

        callback();
    };

    /**
     * This method stops recording Canvas.
     * @param {function} callback - Callback function, that is used to pass recorded blob back to the callee.
     * @method
     * @memberof CanvasRecorder
     * @example
     * recorder.stop(function(blob) {
     *     video.src = URL.createObjectURL(blob);
     * });
     */
    this.stop = function(callback) {
        isRecording = false;

        var that = this;

        if (isCanvasSupportsStreamCapturing && mediaStreamRecorder) {
            mediaStreamRecorder.stop(callback);
            return;
        }

        this.getWebPImages(function() {
            /**
             * @property {Blob} blob - Recorded frames in video/webm blob.
             * @memberof CanvasRecorder
             * @example
             * recorder.stop(function() {
             *     var blob = recorder.blob;
             * });
             */
            whammy.compile(function(blob) {
                if (!config.disableLogs) {
                    console.log('Recording finished!');
                }

                that.blob = blob;

                if (that.blob.forEach) {
                    that.blob = new Blob([], {
                        type: 'video/webm'
                    });
                }

                if (callback) {
                    callback(that.blob);
                }

                whammy.frames = [];
            });
        });
    };

    var isPausedRecording = false;

    /**
     * This method pauses the recording process.
     * @method
     * @memberof CanvasRecorder
     * @example
     * recorder.pause();
     */
    this.pause = function() {
        isPausedRecording = true;

        if (mediaStreamRecorder instanceof MediaStreamRecorder) {
            mediaStreamRecorder.pause();
            return;
        }
    };

    /**
     * This method resumes the recording process.
     * @method
     * @memberof CanvasRecorder
     * @example
     * recorder.resume();
     */
    this.resume = function() {
        isPausedRecording = false;

        if (mediaStreamRecorder instanceof MediaStreamRecorder) {
            mediaStreamRecorder.resume();
            return;
        }

        if (!isRecording) {
            this.record();
        }
    };

    /**
     * This method resets currently recorded data.
     * @method
     * @memberof CanvasRecorder
     * @example
     * recorder.clearRecordedData();
     */
    this.clearRecordedData = function() {
        this.pause();
        whammy.frames = [];
    };

    // for debugging
    this.name = 'CanvasRecorder';
    this.toString = function() {
        return this.name;
    };

    function cloneCanvas() {
        //create a new canvas
        var newCanvas = document.createElement('canvas');
        var context = newCanvas.getContext('2d');

        //set dimensions
        newCanvas.width = htmlElement.width;
        newCanvas.height = htmlElement.height;

        //apply the old canvas to the new one
        context.drawImage(htmlElement, 0, 0);

        //return the new canvas
        return newCanvas;
    }

    function drawCanvasFrame() {
        if (isPausedRecording) {
            lastTime = new Date().getTime();
            return setTimeout(drawCanvasFrame, 500);
        }

        if (htmlElement.nodeName.toLowerCase() === 'canvas') {
            var duration = new Date().getTime() - lastTime;
            // via #206, by Jack i.e. @Seymourr
            lastTime = new Date().getTime();

            whammy.frames.push({
                image: cloneCanvas(),
                duration: duration
            });

            if (isRecording) {
                setTimeout(drawCanvasFrame, config.frameInterval);
            }
            return;
        }

        html2canvas(htmlElement, {
            grabMouse: typeof config.showMousePointer === 'undefined' || config.showMousePointer,
            onrendered: function(canvas) {
                var duration = new Date().getTime() - lastTime;
                if (!duration) {
                    return setTimeout(drawCanvasFrame, config.frameInterval);
                }

                // via #206, by Jack i.e. @Seymourr
                lastTime = new Date().getTime();

                whammy.frames.push({
                    image: canvas.toDataURL('image/webp', 1),
                    duration: duration
                });

                if (isRecording) {
                    setTimeout(drawCanvasFrame, config.frameInterval);
                }
            }
        });
    }

    var lastTime = new Date().getTime();

    var whammy = new Whammy.Video(100);
}

if (typeof RecordRTC !== 'undefined') {
    RecordRTC.CanvasRecorder = CanvasRecorder;
}

// _________________
// WhammyRecorder.js

/**
 * WhammyRecorder is a standalone class used by {@link RecordRTC} to bring video recording in Chrome. It runs top over {@link Whammy}.
 * @summary Video recording feature in Chrome.
 * @license {@link https://github.com/muaz-khan/RecordRTC#license|MIT}
 * @author {@link http://www.MuazKhan.com|Muaz Khan}
 * @typedef WhammyRecorder
 * @class
 * @example
 * var recorder = new WhammyRecorder(mediaStream);
 * recorder.record();
 * recorder.stop(function(blob) {
 *     video.src = URL.createObjectURL(blob);
 * });
 * @see {@link https://github.com/muaz-khan/RecordRTC|RecordRTC Source Code}
 * @param {MediaStream} mediaStream - MediaStream object fetched using getUserMedia API or generated using captureStreamUntilEnded or WebAudio API.
 * @param {object} config - {disableLogs: true, initCallback: function, video: HTMLVideoElement, etc.}
 */

function WhammyRecorder(mediaStream, config) {

    config = config || {};

    if (!config.frameInterval) {
        config.frameInterval = 10;
    }

    if (!config.disableLogs) {
        console.log('Using frames-interval:', config.frameInterval);
    }

    /**
     * This method records video.
     * @method
     * @memberof WhammyRecorder
     * @example
     * recorder.record();
     */
    this.record = function() {
        if (!config.width) {
            config.width = 320;
        }

        if (!config.height) {
            config.height = 240;
        }

        if (!config.video) {
            config.video = {
                width: config.width,
                height: config.height
            };
        }

        if (!config.canvas) {
            config.canvas = {
                width: config.width,
                height: config.height
            };
        }

        canvas.width = config.canvas.width || 320;
        canvas.height = config.canvas.height || 240;

        context = canvas.getContext('2d');

        // setting defaults
        if (config.video && config.video instanceof HTMLVideoElement) {
            video = config.video.cloneNode();

            if (config.initCallback) {
                config.initCallback();
            }
        } else {
            video = document.createElement('video');

            if (typeof video.srcObject !== 'undefined') {
                video.srcObject = mediaStream;
            } else {
                video.src = URL.createObjectURL(mediaStream);
            }

            video.onloadedmetadata = function() { // "onloadedmetadata" may NOT work in FF?
                if (config.initCallback) {
                    config.initCallback();
                }
            };

            video.width = config.video.width;
            video.height = config.video.height;
        }

        video.muted = true;
        video.play();

        lastTime = new Date().getTime();
        whammy = new Whammy.Video();

        if (!config.disableLogs) {
            console.log('canvas resolutions', canvas.width, '*', canvas.height);
            console.log('video width/height', video.width || canvas.width, '*', video.height || canvas.height);
        }

        drawFrames(config.frameInterval);
    };

    /**
     * Draw and push frames to Whammy
     * @param {integer} frameInterval - set minimum interval (in milliseconds) between each time we push a frame to Whammy
     */
    function drawFrames(frameInterval) {
        frameInterval = typeof frameInterval !== 'undefined' ? frameInterval : 10;

        var duration = new Date().getTime() - lastTime;
        if (!duration) {
            return setTimeout(drawFrames, frameInterval, frameInterval);
        }

        if (isPausedRecording) {
            lastTime = new Date().getTime();
            return setTimeout(drawFrames, 100);
        }

        // via #206, by Jack i.e. @Seymourr
        lastTime = new Date().getTime();

        if (video.paused) {
            // via: https://github.com/muaz-khan/WebRTC-Experiment/pull/316
            // Tweak for Android Chrome
            video.play();
        }

        context.drawImage(video, 0, 0, canvas.width, canvas.height);
        whammy.frames.push({
            duration: duration,
            image: canvas.toDataURL('image/webp')
        });

        if (!isStopDrawing) {
            setTimeout(drawFrames, frameInterval, frameInterval);
        }
    }

    function asyncLoop(o) {
        var i = -1,
            length = o.length;

        (function loop() {
            i++;
            if (i === length) {
                o.callback();
                return;
            }

            // "setTimeout" added by Jim McLeod
            setTimeout(function() {
                o.functionToLoop(loop, i);
            }, 1);
        })();
    }


    /**
     * remove black frames from the beginning to the specified frame
     * @param {Array} _frames - array of frames to be checked
     * @param {number} _framesToCheck - number of frame until check will be executed (-1 - will drop all frames until frame not matched will be found)
     * @param {number} _pixTolerance - 0 - very strict (only black pixel color) ; 1 - all
     * @param {number} _frameTolerance - 0 - very strict (only black frame color) ; 1 - all
     * @returns {Array} - array of frames
     */
    // pull#293 by @volodalexey
    function dropBlackFrames(_frames, _framesToCheck, _pixTolerance, _frameTolerance, callback) {
        var localCanvas = document.createElement('canvas');
        localCanvas.width = canvas.width;
        localCanvas.height = canvas.height;
        var context2d = localCanvas.getContext('2d');
        var resultFrames = [];

        var checkUntilNotBlack = _framesToCheck === -1;
        var endCheckFrame = (_framesToCheck && _framesToCheck > 0 && _framesToCheck <= _frames.length) ?
            _framesToCheck : _frames.length;
        var sampleColor = {
            r: 0,
            g: 0,
            b: 0
        };
        var maxColorDifference = Math.sqrt(
            Math.pow(255, 2) +
            Math.pow(255, 2) +
            Math.pow(255, 2)
        );
        var pixTolerance = _pixTolerance && _pixTolerance >= 0 && _pixTolerance <= 1 ? _pixTolerance : 0;
        var frameTolerance = _frameTolerance && _frameTolerance >= 0 && _frameTolerance <= 1 ? _frameTolerance : 0;
        var doNotCheckNext = false;

        asyncLoop({
            length: endCheckFrame,
            functionToLoop: function(loop, f) {
                var matchPixCount, endPixCheck, maxPixCount;

                var finishImage = function() {
                    if (!doNotCheckNext && maxPixCount - matchPixCount <= maxPixCount * frameTolerance) {
                        // console.log('removed black frame : ' + f + ' ; frame duration ' + _frames[f].duration);
                    } else {
                        // console.log('frame is passed : ' + f);
                        if (checkUntilNotBlack) {
                            doNotCheckNext = true;
                        }
                        resultFrames.push(_frames[f]);
                    }
                    loop();
                };

                if (!doNotCheckNext) {
                    var image = new Image();
                    image.onload = function() {
                        context2d.drawImage(image, 0, 0, canvas.width, canvas.height);
                        var imageData = context2d.getImageData(0, 0, canvas.width, canvas.height);
                        matchPixCount = 0;
                        endPixCheck = imageData.data.length;
                        maxPixCount = imageData.data.length / 4;

                        for (var pix = 0; pix < endPixCheck; pix += 4) {
                            var currentColor = {
                                r: imageData.data[pix],
                                g: imageData.data[pix + 1],
                                b: imageData.data[pix + 2]
                            };
                            var colorDifference = Math.sqrt(
                                Math.pow(currentColor.r - sampleColor.r, 2) +
                                Math.pow(currentColor.g - sampleColor.g, 2) +
                                Math.pow(currentColor.b - sampleColor.b, 2)
                            );
                            // difference in color it is difference in color vectors (r1,g1,b1) <=> (r2,g2,b2)
                            if (colorDifference <= maxColorDifference * pixTolerance) {
                                matchPixCount++;
                            }
                        }
                        finishImage();
                    };
                    image.src = _frames[f].image;
                } else {
                    finishImage();
                }
            },
            callback: function() {
                resultFrames = resultFrames.concat(_frames.slice(endCheckFrame));

                if (resultFrames.length <= 0) {
                    // at least one last frame should be available for next manipulation
                    // if total duration of all frames will be < 1000 than ffmpeg doesn't work well...
                    resultFrames.push(_frames[_frames.length - 1]);
                }
                callback(resultFrames);
            }
        });
    }

    var isStopDrawing = false;

    /**
     * This method stops recording video.
     * @param {function} callback - Callback function, that is used to pass recorded blob back to the callee.
     * @method
     * @memberof WhammyRecorder
     * @example
     * recorder.stop(function(blob) {
     *     video.src = URL.createObjectURL(blob);
     * });
     */
    this.stop = function(callback) {
        isStopDrawing = true;

        var _this = this;
        // analyse of all frames takes some time!
        setTimeout(function() {
            // e.g. dropBlackFrames(frames, 10, 1, 1) - will cut all 10 frames
            // e.g. dropBlackFrames(frames, 10, 0.5, 0.5) - will analyse 10 frames
            // e.g. dropBlackFrames(frames, 10) === dropBlackFrames(frames, 10, 0, 0) - will analyse 10 frames with strict black color
            dropBlackFrames(whammy.frames, -1, null, null, function(frames) {
                whammy.frames = frames;

                // to display advertisement images!
                if (config.advertisement && config.advertisement.length) {
                    whammy.frames = config.advertisement.concat(whammy.frames);
                }

                /**
                 * @property {Blob} blob - Recorded frames in video/webm blob.
                 * @memberof WhammyRecorder
                 * @example
                 * recorder.stop(function() {
                 *     var blob = recorder.blob;
                 * });
                 */
                whammy.compile(function(blob) {
                    _this.blob = blob;

                    if (_this.blob.forEach) {
                        _this.blob = new Blob([], {
                            type: 'video/webm'
                        });
                    }

                    if (callback) {
                        callback(_this.blob);
                    }
                });
            });
        }, 10);
    };

    var isPausedRecording = false;

    /**
     * This method pauses the recording process.
     * @method
     * @memberof WhammyRecorder
     * @example
     * recorder.pause();
     */
    this.pause = function() {
        isPausedRecording = true;
    };

    /**
     * This method resumes the recording process.
     * @method
     * @memberof WhammyRecorder
     * @example
     * recorder.resume();
     */
    this.resume = function() {
        isPausedRecording = false;

        if (isStopDrawing) {
            this.record();
        }
    };

    /**
     * This method resets currently recorded data.
     * @method
     * @memberof WhammyRecorder
     * @example
     * recorder.clearRecordedData();
     */
    this.clearRecordedData = function() {
        this.pause();
        whammy.frames = [];
    };

    // for debugging
    this.name = 'WhammyRecorder';
    this.toString = function() {
        return this.name;
    };

    var canvas = document.createElement('canvas');
    var context = canvas.getContext('2d');

    var video;
    var lastTime;
    var whammy;
}

if (typeof RecordRTC !== 'undefined') {
    RecordRTC.WhammyRecorder = WhammyRecorder;
}

// https://github.com/antimatter15/whammy/blob/master/LICENSE
// _________
// Whammy.js

// todo: Firefox now supports webp for webm containers!
// their MediaRecorder implementation works well!
// should we provide an option to record via Whammy.js or MediaRecorder API is a better solution?

/**
 * Whammy is a standalone class used by {@link RecordRTC} to bring video recording in Chrome. It is written by {@link https://github.com/antimatter15|antimatter15}
 * @summary A real time javascript webm encoder based on a canvas hack.
 * @license {@link https://github.com/muaz-khan/RecordRTC#license|MIT}
 * @author {@link http://www.MuazKhan.com|Muaz Khan}
 * @typedef Whammy
 * @class
 * @example
 * var recorder = new Whammy().Video(15);
 * recorder.add(context || canvas || dataURL);
 * var output = recorder.compile();
 * @see {@link https://github.com/muaz-khan/RecordRTC|RecordRTC Source Code}
 */

var Whammy = (function() {
    // a more abstract-ish API

    function WhammyVideo(duration) {
        this.frames = [];
        this.duration = duration || 1;
        this.quality = 0.8;
    }

    /**
     * Pass Canvas or Context or image/webp(string) to {@link Whammy} encoder.
     * @method
     * @memberof Whammy
     * @example
     * recorder = new Whammy().Video(0.8, 100);
     * recorder.add(canvas || context || 'image/webp');
     * @param {string} frame - Canvas || Context || image/webp
     * @param {number} duration - Stick a duration (in milliseconds)
     */
    WhammyVideo.prototype.add = function(frame, duration) {
        if ('canvas' in frame) { //CanvasRenderingContext2D
            frame = frame.canvas;
        }

        if ('toDataURL' in frame) {
            frame = frame.toDataURL('image/webp', this.quality);
        }

        if (!(/^data:image\/webp;base64,/ig).test(frame)) {
            throw 'Input must be formatted properly as a base64 encoded DataURI of type image/webp';
        }
        this.frames.push({
            image: frame,
            duration: duration || this.duration
        });
    };

    function processInWebWorker(_function) {
        var blob = URL.createObjectURL(new Blob([_function.toString(),
            'this.onmessage =  function (e) {' + _function.name + '(e.data);}'
        ], {
            type: 'application/javascript'
        }));

        var worker = new Worker(blob);
        URL.revokeObjectURL(blob);
        return worker;
    }

    function whammyInWebWorker(frames) {
        function ArrayToWebM(frames) {
            var info = checkFrames(frames);
            if (!info) {
                return [];
            }

            var clusterMaxDuration = 30000;

            var EBML = [{
                'id': 0x1a45dfa3, // EBML
                'data': [{
                    'data': 1,
                    'id': 0x4286 // EBMLVersion
                }, {
                    'data': 1,
                    'id': 0x42f7 // EBMLReadVersion
                }, {
                    'data': 4,
                    'id': 0x42f2 // EBMLMaxIDLength
                }, {
                    'data': 8,
                    'id': 0x42f3 // EBMLMaxSizeLength
                }, {
                    'data': 'webm',
                    'id': 0x4282 // DocType
                }, {
                    'data': 2,
                    'id': 0x4287 // DocTypeVersion
                }, {
                    'data': 2,
                    'id': 0x4285 // DocTypeReadVersion
                }]
            }, {
                'id': 0x18538067, // Segment
                'data': [{
                    'id': 0x1549a966, // Info
                    'data': [{
                        'data': 1e6, //do things in millisecs (num of nanosecs for duration scale)
                        'id': 0x2ad7b1 // TimecodeScale
                    }, {
                        'data': 'whammy',
                        'id': 0x4d80 // MuxingApp
                    }, {
                        'data': 'whammy',
                        'id': 0x5741 // WritingApp
                    }, {
                        'data': doubleToString(info.duration),
                        'id': 0x4489 // Duration
                    }]
                }, {
                    'id': 0x1654ae6b, // Tracks
                    'data': [{
                        'id': 0xae, // TrackEntry
                        'data': [{
                            'data': 1,
                            'id': 0xd7 // TrackNumber
                        }, {
                            'data': 1,
                            'id': 0x73c5 // TrackUID
                        }, {
                            'data': 0,
                            'id': 0x9c // FlagLacing
                        }, {
                            'data': 'und',
                            'id': 0x22b59c // Language
                        }, {
                            'data': 'V_VP8',
                            'id': 0x86 // CodecID
                        }, {
                            'data': 'VP8',
                            'id': 0x258688 // CodecName
                        }, {
                            'data': 1,
                            'id': 0x83 // TrackType
                        }, {
                            'id': 0xe0, // Video
                            'data': [{
                                'data': info.width,
                                'id': 0xb0 // PixelWidth
                            }, {
                                'data': info.height,
                                'id': 0xba // PixelHeight
                            }]
                        }]
                    }]
                }]
            }];

            //Generate clusters (max duration)
            var frameNumber = 0;
            var clusterTimecode = 0;
            while (frameNumber < frames.length) {

                var clusterFrames = [];
                var clusterDuration = 0;
                do {
                    clusterFrames.push(frames[frameNumber]);
                    clusterDuration += frames[frameNumber].duration;
                    frameNumber++;
                } while (frameNumber < frames.length && clusterDuration < clusterMaxDuration);

                var clusterCounter = 0;
                var cluster = {
                    'id': 0x1f43b675, // Cluster
                    'data': getClusterData(clusterTimecode, clusterCounter, clusterFrames)
                }; //Add cluster to segment
                EBML[1].data.push(cluster);
                clusterTimecode += clusterDuration;
            }

            return generateEBML(EBML);
        }

        function getClusterData(clusterTimecode, clusterCounter, clusterFrames) {
            return [{
                'data': clusterTimecode,
                'id': 0xe7 // Timecode
            }].concat(clusterFrames.map(function(webp) {
                var block = makeSimpleBlock({
                    discardable: 0,
                    frame: webp.data.slice(4),
                    invisible: 0,
                    keyframe: 1,
                    lacing: 0,
                    trackNum: 1,
                    timecode: Math.round(clusterCounter)
                });
                clusterCounter += webp.duration;
                return {
                    data: block,
                    id: 0xa3
                };
            }));
        }

        // sums the lengths of all the frames and gets the duration

        function checkFrames(frames) {
            if (!frames[0]) {
                postMessage({
                    error: 'Something went wrong. Maybe WebP format is not supported in the current browser.'
                });
                return;
            }

            var width = frames[0].width,
                height = frames[0].height,
                duration = frames[0].duration;

            for (var i = 1; i < frames.length; i++) {
                duration += frames[i].duration;
            }
            return {
                duration: duration,
                width: width,
                height: height
            };
        }

        function numToBuffer(num) {
            var parts = [];
            while (num > 0) {
                parts.push(num & 0xff);
                num = num >> 8;
            }
            return new Uint8Array(parts.reverse());
        }

        function strToBuffer(str) {
            return new Uint8Array(str.split('').map(function(e) {
                return e.charCodeAt(0);
            }));
        }

        function bitsToBuffer(bits) {
            var data = [];
            var pad = (bits.length % 8) ? (new Array(1 + 8 - (bits.length % 8))).join('0') : '';
            bits = pad + bits;
            for (var i = 0; i < bits.length; i += 8) {
                data.push(parseInt(bits.substr(i, 8), 2));
            }
            return new Uint8Array(data);
        }

        function generateEBML(json) {
            var ebml = [];
            for (var i = 0; i < json.length; i++) {
                var data = json[i].data;

                if (typeof data === 'object') {
                    data = generateEBML(data);
                }

                if (typeof data === 'number') {
                    data = bitsToBuffer(data.toString(2));
                }

                if (typeof data === 'string') {
                    data = strToBuffer(data);
                }

                var len = data.size || data.byteLength || data.length;
                var zeroes = Math.ceil(Math.ceil(Math.log(len) / Math.log(2)) / 8);
                var sizeToString = len.toString(2);
                var padded = (new Array((zeroes * 7 + 7 + 1) - sizeToString.length)).join('0') + sizeToString;
                var size = (new Array(zeroes)).join('0') + '1' + padded;

                ebml.push(numToBuffer(json[i].id));
                ebml.push(bitsToBuffer(size));
                ebml.push(data);
            }

            return new Blob(ebml, {
                type: 'video/webm'
            });
        }

        function toBinStrOld(bits) {
            var data = '';
            var pad = (bits.length % 8) ? (new Array(1 + 8 - (bits.length % 8))).join('0') : '';
            bits = pad + bits;
            for (var i = 0; i < bits.length; i += 8) {
                data += String.fromCharCode(parseInt(bits.substr(i, 8), 2));
            }
            return data;
        }

        function makeSimpleBlock(data) {
            var flags = 0;

            if (data.keyframe) {
                flags |= 128;
            }

            if (data.invisible) {
                flags |= 8;
            }

            if (data.lacing) {
                flags |= (data.lacing << 1);
            }

            if (data.discardable) {
                flags |= 1;
            }

            if (data.trackNum > 127) {
                throw 'TrackNumber > 127 not supported';
            }

            var out = [data.trackNum | 0x80, data.timecode >> 8, data.timecode & 0xff, flags].map(function(e) {
                return String.fromCharCode(e);
            }).join('') + data.frame;

            return out;
        }

        function parseWebP(riff) {
            var VP8 = riff.RIFF[0].WEBP[0];

            var frameStart = VP8.indexOf('\x9d\x01\x2a'); // A VP8 keyframe starts with the 0x9d012a header
            for (var i = 0, c = []; i < 4; i++) {
                c[i] = VP8.charCodeAt(frameStart + 3 + i);
            }

            var width, height, tmp;

            //the code below is literally copied verbatim from the bitstream spec
            tmp = (c[1] << 8) | c[0];
            width = tmp & 0x3FFF;
            tmp = (c[3] << 8) | c[2];
            height = tmp & 0x3FFF;
            return {
                width: width,
                height: height,
                data: VP8,
                riff: riff
            };
        }

        function getStrLength(string, offset) {
            return parseInt(string.substr(offset + 4, 4).split('').map(function(i) {
                var unpadded = i.charCodeAt(0).toString(2);
                return (new Array(8 - unpadded.length + 1)).join('0') + unpadded;
            }).join(''), 2);
        }

        function parseRIFF(string) {
            var offset = 0;
            var chunks = {};

            while (offset < string.length) {
                var id = string.substr(offset, 4);
                var len = getStrLength(string, offset);
                var data = string.substr(offset + 4 + 4, len);
                offset += 4 + 4 + len;
                chunks[id] = chunks[id] || [];

                if (id === 'RIFF' || id === 'LIST') {
                    chunks[id].push(parseRIFF(data));
                } else {
                    chunks[id].push(data);
                }
            }
            return chunks;
        }

        function doubleToString(num) {
            return [].slice.call(
                new Uint8Array((new Float64Array([num])).buffer), 0).map(function(e) {
                return String.fromCharCode(e);
            }).reverse().join('');
        }

        var webm = new ArrayToWebM(frames.map(function(frame) {
            var webp = parseWebP(parseRIFF(atob(frame.image.slice(23))));
            webp.duration = frame.duration;
            return webp;
        }));

        postMessage(webm);
    }

    /**
     * Encodes frames in WebM container. It uses WebWorkinvoke to invoke 'ArrayToWebM' method.
     * @param {function} callback - Callback function, that is used to pass recorded blob back to the callee.
     * @method
     * @memberof Whammy
     * @example
     * recorder = new Whammy().Video(0.8, 100);
     * recorder.compile(function(blob) {
     *    // blob.size - blob.type
     * });
     */
    WhammyVideo.prototype.compile = function(callback) {
        var webWorker = processInWebWorker(whammyInWebWorker);

        webWorker.onmessage = function(event) {
            if (event.data.error) {
                console.error(event.data.error);
                return;
            }
            callback(event.data);
        };

        webWorker.postMessage(this.frames);
    };

    return {
        /**
         * A more abstract-ish API.
         * @method
         * @memberof Whammy
         * @example
         * recorder = new Whammy().Video(0.8, 100);
         * @param {?number} speed - 0.8
         * @param {?number} quality - 100
         */
        Video: WhammyVideo
    };
})();

if (typeof RecordRTC !== 'undefined') {
    RecordRTC.Whammy = Whammy;
}

// ______________ (indexed-db)
// DiskStorage.js

/**
 * DiskStorage is a standalone object used by {@link RecordRTC} to store recorded blobs in IndexedDB storage.
 * @summary Writing blobs into IndexedDB.
 * @license {@link https://github.com/muaz-khan/RecordRTC#license|MIT}
 * @author {@link http://www.MuazKhan.com|Muaz Khan}
 * @example
 * DiskStorage.Store({
 *     audioBlob: yourAudioBlob,
 *     videoBlob: yourVideoBlob,
 *     gifBlob  : yourGifBlob
 * });
 * DiskStorage.Fetch(function(dataURL, type) {
 *     if(type === 'audioBlob') { }
 *     if(type === 'videoBlob') { }
 *     if(type === 'gifBlob')   { }
 * });
 * // DiskStorage.dataStoreName = 'recordRTC';
 * // DiskStorage.onError = function(error) { };
 * @property {function} init - This method must be called once to initialize IndexedDB ObjectStore. Though, it is auto-used internally.
 * @property {function} Fetch - This method fetches stored blobs from IndexedDB.
 * @property {function} Store - This method stores blobs in IndexedDB.
 * @property {function} onError - This function is invoked for any known/unknown error.
 * @property {string} dataStoreName - Name of the ObjectStore created in IndexedDB storage.
 * @see {@link https://github.com/muaz-khan/RecordRTC|RecordRTC Source Code}
 */


var DiskStorage = {
    /**
     * This method must be called once to initialize IndexedDB ObjectStore. Though, it is auto-used internally.
     * @method
     * @memberof DiskStorage
     * @internal
     * @example
     * DiskStorage.init();
     */
    init: function() {
        var self = this;

        if (typeof indexedDB === 'undefined' || typeof indexedDB.open === 'undefined') {
            console.error('IndexedDB API are not available in this browser.');
            return;
        }

        var dbVersion = 1;
        var dbName = this.dbName || location.href.replace(/\/|:|#|%|\.|\[|\]/g, ''),
            db;
        var request = indexedDB.open(dbName, dbVersion);

        function createObjectStore(dataBase) {
            dataBase.createObjectStore(self.dataStoreName);
        }

        function putInDB() {
            var transaction = db.transaction([self.dataStoreName], 'readwrite');

            if (self.videoBlob) {
                transaction.objectStore(self.dataStoreName).put(self.videoBlob, 'videoBlob');
            }

            if (self.gifBlob) {
                transaction.objectStore(self.dataStoreName).put(self.gifBlob, 'gifBlob');
            }

            if (self.audioBlob) {
                transaction.objectStore(self.dataStoreName).put(self.audioBlob, 'audioBlob');
            }

            function getFromStore(portionName) {
                transaction.objectStore(self.dataStoreName).get(portionName).onsuccess = function(event) {
                    if (self.callback) {
                        self.callback(event.target.result, portionName);
                    }
                };
            }

            getFromStore('audioBlob');
            getFromStore('videoBlob');
            getFromStore('gifBlob');
        }

        request.onerror = self.onError;

        request.onsuccess = function() {
            db = request.result;
            db.onerror = self.onError;

            if (db.setVersion) {
                if (db.version !== dbVersion) {
                    var setVersion = db.setVersion(dbVersion);
                    setVersion.onsuccess = function() {
                        createObjectStore(db);
                        putInDB();
                    };
                } else {
                    putInDB();
                }
            } else {
                putInDB();
            }
        };
        request.onupgradeneeded = function(event) {
            createObjectStore(event.target.result);
        };
    },
    /**
     * This method fetches stored blobs from IndexedDB.
     * @method
     * @memberof DiskStorage
     * @internal
     * @example
     * DiskStorage.Fetch(function(dataURL, type) {
     *     if(type === 'audioBlob') { }
     *     if(type === 'videoBlob') { }
     *     if(type === 'gifBlob')   { }
     * });
     */
    Fetch: function(callback) {
        this.callback = callback;
        this.init();

        return this;
    },
    /**
     * This method stores blobs in IndexedDB.
     * @method
     * @memberof DiskStorage
     * @internal
     * @example
     * DiskStorage.Store({
     *     audioBlob: yourAudioBlob,
     *     videoBlob: yourVideoBlob,
     *     gifBlob  : yourGifBlob
     * });
     */
    Store: function(config) {
        this.audioBlob = config.audioBlob;
        this.videoBlob = config.videoBlob;
        this.gifBlob = config.gifBlob;

        this.init();

        return this;
    },
    /**
     * This function is invoked for any known/unknown error.
     * @method
     * @memberof DiskStorage
     * @internal
     * @example
     * DiskStorage.onError = function(error){
     *     alerot( JSON.stringify(error) );
     * };
     */
    onError: function(error) {
        console.error(JSON.stringify(error, null, '\t'));
    },

    /**
     * @property {string} dataStoreName - Name of the ObjectStore created in IndexedDB storage.
     * @memberof DiskStorage
     * @internal
     * @example
     * DiskStorage.dataStoreName = 'recordRTC';
     */
    dataStoreName: 'recordRTC',
    dbName: null
};

if (typeof RecordRTC !== 'undefined') {
    RecordRTC.DiskStorage = DiskStorage;
}

// ______________
// GifRecorder.js

/**
 * GifRecorder is standalone calss used by {@link RecordRTC} to record video or canvas into animated gif.
 * @license {@link https://github.com/muaz-khan/RecordRTC#license|MIT}
 * @author {@link http://www.MuazKhan.com|Muaz Khan}
 * @typedef GifRecorder
 * @class
 * @example
 * var recorder = new GifRecorder(mediaStream || canvas || context, { width: 1280, height: 720, frameRate: 200, quality: 10 });
 * recorder.record();
 * recorder.stop(function(blob) {
 *     img.src = URL.createObjectURL(blob);
 * });
 * @see {@link https://github.com/muaz-khan/RecordRTC|RecordRTC Source Code}
 * @param {MediaStream} mediaStream - MediaStream object or HTMLCanvasElement or CanvasRenderingContext2D.
 * @param {object} config - {disableLogs:true, initCallback: function, width: 320, height: 240, frameRate: 200, quality: 10}
 */

function GifRecorder(mediaStream, config) {
    if (typeof GIFEncoder === 'undefined') {
        throw 'Please link: https://cdn.webrtc-experiment.com/gif-recorder.js';
    }

    config = config || {};

    var isHTMLObject = mediaStream instanceof CanvasRenderingContext2D || mediaStream instanceof HTMLCanvasElement;

    /**
     * This method records MediaStream.
     * @method
     * @memberof GifRecorder
     * @example
     * recorder.record();
     */
    this.record = function() {
        if (!isHTMLObject) {
            if (!config.width) {
                config.width = video.offsetWidth || 320;
            }

            if (!this.height) {
                config.height = video.offsetHeight || 240;
            }

            if (!config.video) {
                config.video = {
                    width: config.width,
                    height: config.height
                };
            }

            if (!config.canvas) {
                config.canvas = {
                    width: config.width,
                    height: config.height
                };
            }

            canvas.width = config.canvas.width || 320;
            canvas.height = config.canvas.height || 240;

            video.width = config.video.width || 320;
            video.height = config.video.height || 240;
        }

        // external library to record as GIF images
        gifEncoder = new GIFEncoder();

        // void setRepeat(int iter) 
        // Sets the number of times the set of GIF frames should be played. 
        // Default is 1; 0 means play indefinitely.
        gifEncoder.setRepeat(0);

        // void setFrameRate(Number fps) 
        // Sets frame rate in frames per second. 
        // Equivalent to setDelay(1000/fps).
        // Using "setDelay" instead of "setFrameRate"
        gifEncoder.setDelay(config.frameRate || 200);

        // void setQuality(int quality) 
        // Sets quality of color quantization (conversion of images to the 
        // maximum 256 colors allowed by the GIF specification). 
        // Lower values (minimum = 1) produce better colors, 
        // but slow processing significantly. 10 is the default, 
        // and produces good color mapping at reasonable speeds. 
        // Values greater than 20 do not yield significant improvements in speed.
        gifEncoder.setQuality(config.quality || 10);

        // Boolean start() 
        // This writes the GIF Header and returns false if it fails.
        gifEncoder.start();

        startTime = Date.now();

        var self = this;

        function drawVideoFrame(time) {
            if (isPausedRecording) {
                return setTimeout(function() {
                    drawVideoFrame(time);
                }, 100);
            }

            lastAnimationFrame = requestAnimationFrame(drawVideoFrame);

            if (typeof lastFrameTime === undefined) {
                lastFrameTime = time;
            }

            // ~10 fps
            if (time - lastFrameTime < 90) {
                return;
            }

            if (!isHTMLObject && video.paused) {
                // via: https://github.com/muaz-khan/WebRTC-Experiment/pull/316
                // Tweak for Android Chrome
                video.play();
            }

            if (!isHTMLObject) {
                context.drawImage(video, 0, 0, canvas.width, canvas.height);
            }

            if (config.onGifPreview) {
                config.onGifPreview(canvas.toDataURL('image/png'));
            }

            gifEncoder.addFrame(context);
            lastFrameTime = time;
        }

        lastAnimationFrame = requestAnimationFrame(drawVideoFrame);

        if (config.initCallback) {
            config.initCallback();
        }
    };

    /**
     * This method stops recording MediaStream.
     * @param {function} callback - Callback function, that is used to pass recorded blob back to the callee.
     * @method
     * @memberof GifRecorder
     * @example
     * recorder.stop(function(blob) {
     *     img.src = URL.createObjectURL(blob);
     * });
     */
    this.stop = function() {
        if (lastAnimationFrame) {
            cancelAnimationFrame(lastAnimationFrame);
        }

        endTime = Date.now();

        /**
         * @property {Blob} blob - The recorded blob object.
         * @memberof GifRecorder
         * @example
         * recorder.stop(function(){
         *     var blob = recorder.blob;
         * });
         */
        this.blob = new Blob([new Uint8Array(gifEncoder.stream().bin)], {
            type: 'image/gif'
        });

        // bug: find a way to clear old recorded blobs
        gifEncoder.stream().bin = [];
    };

    var isPausedRecording = false;

    /**
     * This method pauses the recording process.
     * @method
     * @memberof GifRecorder
     * @example
     * recorder.pause();
     */
    this.pause = function() {
        isPausedRecording = true;
    };

    /**
     * This method resumes the recording process.
     * @method
     * @memberof GifRecorder
     * @example
     * recorder.resume();
     */
    this.resume = function() {
        isPausedRecording = false;
    };

    /**
     * This method resets currently recorded data.
     * @method
     * @memberof GifRecorder
     * @example
     * recorder.clearRecordedData();
     */
    this.clearRecordedData = function() {
        if (!gifEncoder) {
            return;
        }

        this.pause();

        gifEncoder.stream().bin = [];
    };

    // for debugging
    this.name = 'GifRecorder';
    this.toString = function() {
        return this.name;
    };

    var canvas = document.createElement('canvas');
    var context = canvas.getContext('2d');

    if (isHTMLObject) {
        if (mediaStream instanceof CanvasRenderingContext2D) {
            context = mediaStream;
            canvas = context.canvas;
        } else if (mediaStream instanceof HTMLCanvasElement) {
            context = mediaStream.getContext('2d');
            canvas = mediaStream;
        }
    }

    if (!isHTMLObject) {
        var video = document.createElement('video');
        video.muted = true;
        video.autoplay = true;

        if (typeof video.srcObject !== 'undefined') {
            video.srcObject = mediaStream;
        } else {
            video.src = URL.createObjectURL(mediaStream);
        }

        video.play();
    }

    var lastAnimationFrame = null;
    var startTime, endTime, lastFrameTime;

    var gifEncoder;
}

if (typeof RecordRTC !== 'undefined') {
    RecordRTC.GifRecorder = GifRecorder;
}

// ______________________
// MultiStreamRecorder.js

/*
 * Video conference recording, using captureStream API along with WebAudio and Canvas2D API.
 */

/**
 * MultiStreamRecorder can record multiple videos in single container.
 * @summary Multi-videos recorder.
 * @license {@link https://github.com/muaz-khan/RecordRTC#license|MIT}
 * @author {@link http://www.MuazKhan.com|Muaz Khan}
 * @typedef MultiStreamRecorder
 * @class
 * @example
 * var options = {
 *     mimeType: 'video/webm'
 * }
 * var recorder = new MultiStreamRecorder(ArrayOfMediaStreams, options);
 * recorder.record();
 * recorder.stop(function(blob) {
 *     video.src = URL.createObjectURL(blob);
 *
 *     // or
 *     var blob = recorder.blob;
 * });
 * @see {@link https://github.com/muaz-khan/RecordRTC|RecordRTC Source Code}
 * @param {MediaStreams} mediaStreams - Array of MediaStreams.
 * @param {object} config - {disableLogs:true, frameInterval: 1, mimeType: "video/webm"}
 */

function MultiStreamRecorder(arrayOfMediaStreams, options) {
    var self = this;

    options = options || {
        mimeType: 'video/webm',
        video: {
            width: 360,
            height: 240
        }
    };

    if (!options.frameInterval) {
        options.frameInterval = 10;
    }

    if (!options.video) {
        options.video = {};
    }

    if (!options.video.width) {
        options.video.width = 360;
    }

    if (!options.video.height) {
        options.video.height = 240;
    }

    /**
     * This method records all MediaStreams.
     * @method
     * @memberof MultiStreamRecorder
     * @example
     * recorder.record();
     */
    this.record = function() {
        isStoppedRecording = false;
        var mixedVideoStream = getMixedVideoStream();

        var mixedAudioStream = getMixedAudioStream();
        if (mixedAudioStream) {
            mixedAudioStream.getAudioTracks().forEach(function(track) {
                mixedVideoStream.addTrack(track);
            });
        }

        if (options.previewStream && typeof options.previewStream === 'function') {
            options.previewStream(mixedVideoStream);
        }

        mediaRecorder = new MediaStreamRecorder(mixedVideoStream, options);

        drawVideosToCanvas();

        mediaRecorder.record();
    };

    /**
     * This method stops recording MediaStream.
     * @param {function} callback - Callback function, that is used to pass recorded blob back to the callee.
     * @method
     * @memberof MultiStreamRecorder
     * @example
     * recorder.stop(function(blob) {
     *     video.src = URL.createObjectURL(blob);
     * });
     */
    this.stop = function(callback) {
        isStoppedRecording = true;

        if (!mediaRecorder) {
            return;
        }

        mediaRecorder.stop(function(blob) {
            self.blob = blob;

            callback(blob);

            self.clearRecordedData();
        });
    };

    function getMixedAudioStream() {
        // via: @pehrsons
        if (!Storage.AudioContextConstructor) {
            Storage.AudioContextConstructor = new Storage.AudioContext();
        }

        self.audioContext = Storage.AudioContextConstructor;

        self.audioSources = [];

        self.gainNode = self.audioContext.createGain();
        self.gainNode.connect(self.audioContext.destination);
        self.gainNode.gain.value = 0; // don't hear self

        var audioTracksLength = 0;
        arrayOfMediaStreams.forEach(function(stream) {
            if (!stream.getAudioTracks().length) {
                return;
            }

            audioTracksLength++;

            var audioSource = self.audioContext.createMediaStreamSource(stream);
            audioSource.connect(self.gainNode);
            self.audioSources.push(audioSource);
        });

        if (!audioTracksLength) {
            return;
        }

        self.audioDestination = self.audioContext.createMediaStreamDestination();
        self.audioSources.forEach(function(audioSource) {
            audioSource.connect(self.audioDestination);
        });
        return self.audioDestination.stream;
    }

    var videos = [];
    var mediaRecorder;

    function resetVideoStreams(streams) {
        videos = [];
        streams = streams || arrayOfMediaStreams;

        // via: @adrian-ber
        streams.forEach(function(stream) {
            if (!stream.getVideoTracks().length) {
                return;
            }

            var video = getVideo(stream);
            video.width = options.video.width;
            video.height = options.video.height;
            video.stream = stream;
            videos.push(video);
        });
    }

    function getMixedVideoStream() {
        resetVideoStreams();

        var capturedStream;

        if ('captureStream' in canvas) {
            capturedStream = canvas.captureStream();
        } else if ('mozCaptureStream' in canvas) {
            capturedStream = canvas.mozCaptureStream();
        } else if (!options.disableLogs) {
            console.error('Upgrade to latest Chrome or otherwise enable this flag: chrome://flags/#enable-experimental-web-platform-features');
        }

        var videoStream = new MediaStream();

        // via streamproc/MediaStreamRecorder#126
        capturedStream.getVideoTracks().forEach(function(track) {
            videoStream.addTrack(track);
        });

        canvas.stream = videoStream;

        return videoStream;
    }

    function getVideo(stream) {
        var video = document.createElement('video');
        video.src = URL.createObjectURL(stream);
        video.muted = true;
        video.volume = 0;
        video.play();
        return video;
    }

    var isStoppedRecording = false;

    function drawVideosToCanvas() {
        if (isStoppedRecording) {
            return;
        }

        var videosLength = videos.length;

        var fullcanvas = false;
        videos.forEach(function(video) {
            if (!video.stream) {
                video.stream = {};
            }

            if (video.stream.fullcanvas) {
                fullcanvas = video.stream;
            }
        });

        if (fullcanvas) {
            canvas.width = fullcanvas.width;
            canvas.height = fullcanvas.height;
        } else {
            canvas.width = videosLength > 1 ? videos[0].width * 2 : videos[0].width;
            canvas.height = videosLength > 2 ? videos[0].height * 2 : videos[0].height;
        }

        videos.forEach(drawImage);

        setTimeout(drawVideosToCanvas, options.frameInterval);
    }

    function drawImage(video, idx) {
        if (isStoppedRecording) {
            return;
        }

        var x = 0;
        var y = 0;
        var width = video.width;
        var height = video.height;

        if (idx === 1) {
            x = video.width;
        }

        if (idx === 2) {
            y = video.height;
        }

        if (idx === 3) {
            x = video.width;
            y = video.height;
        }

        if (typeof video.stream.left !== 'undefined') {
            x = video.stream.left;
        }

        if (typeof video.stream.top !== 'undefined') {
            y = video.stream.top;
        }

        if (typeof video.stream.width !== 'undefined') {
            width = video.stream.width;
        }

        if (typeof video.stream.height !== 'undefined') {
            height = video.stream.height;
        }

        context.drawImage(video, x, y, width, height);

        if (typeof video.stream.onRender === 'function') {
            video.stream.onRender(context, x, y, width, height, idx);
        }
    }

    var canvas = document.createElement('canvas');
    var context = canvas.getContext('2d');

    canvas.style = 'opacity:0;position:absolute;z-index:-1;top: -100000000;left:-1000000000;';

    (document.body || document.documentElement).appendChild(canvas);

    /**
     * This method pauses the recording process.
     * @method
     * @memberof MultiStreamRecorder
     * @example
     * recorder.pause();
     */
    this.pause = function() {
        if (mediaRecorder) {
            mediaRecorder.pause();
        }
    };

    /**
     * This method resumes the recording process.
     * @method
     * @memberof MultiStreamRecorder
     * @example
     * recorder.resume();
     */
    this.resume = function() {
        if (mediaRecorder) {
            mediaRecorder.resume();
        }
    };

    /**
     * This method resets currently recorded data.
     * @method
     * @memberof MultiStreamRecorder
     * @example
     * recorder.clearRecordedData();
     */
    this.clearRecordedData = function() {
        videos = [];
        isStoppedRecording = true;

        if (mediaRecorder) {
            mediaRecorder.clearRecordedData();
        }

        mediaRecorder = null;

        if (self.gainNode) {
            self.gainNode.disconnect();
            self.gainNode = null;
        }

        if (self.audioSources.length) {
            self.audioSources.forEach(function(source) {
                source.disconnect();
            });
            self.audioSources = [];
        }

        if (self.audioDestination) {
            self.audioDestination.disconnect();
            self.audioDestination = null;
        }

        self.audioContext = null;

        context.clearRect(0, 0, canvas.width, canvas.height);

        if (canvas.stream) {
            canvas.stream.stop();
            canvas.stream = null;
        }
    };

    /**
     * Add extra media-streams to existing recordings.
     * @method
     * @memberof MultiStreamRecorder
     * @param {MediaStreams} mediaStreams - Array of MediaStreams
     * @example
     * recorder.addStreams([newAudioStream, newVideoStream]);
     */
    this.addStreams = function(streams) {
        if (!streams) {
            throw 'First parameter is required.';
        }

        if (!(streams instanceof Array)) {
            streams = [streams];
        }

        arrayOfMediaStreams.concat(streams);

        if (!mediaRecorder) {
            return;
        }

        streams.forEach(function(stream) {
            if (stream.getVideoTracks().length) {
                var video = getVideo(stream);
                video.width = options.video.width;
                video.height = options.video.height;
                video.stream = stream;
                videos.push(video);
            }

            if (stream.getAudioTracks().length && self.audioContext) {
                var audioSource = self.audioContext.createMediaStreamSource(stream);
                audioSource.connect(self.audioDestination);
                self.audioSources.push(audioSource);
            }
        });
    };

    /**
     * Reset videos during live recording. Replace old videos e.g. replace cameras with full-screen.
     * @method
     * @memberof MultiStreamRecorder
     * @param {MediaStreams} mediaStreams - Array of MediaStreams
     * @example
     * recorder.resetVideoStreams([newVideo1, newVideo2]);
     */
    this.resetVideoStreams = function(streams) {
        if (streams && !(streams instanceof Array)) {
            streams = [streams];
        }

        resetVideoStreams(streams);
    };

    // for debugging
    this.name = 'MultiStreamRecorder';
    this.toString = function() {
        return this.name;
    };
}

if (typeof RecordRTC !== 'undefined') {
    RecordRTC.MultiStreamRecorder = MultiStreamRecorder;
}

// _____________________
// RecordRTC.promises.js

/**
 * RecordRTCPromisesHandler adds promises support in {@link RecordRTC}. Try a {@link https://github.com/muaz-khan/RecordRTC/blob/master/simple-demos/RecordRTCPromisesHandler.html|demo here}
 * @summary Promises for {@link RecordRTC}
 * @license {@link https://github.com/muaz-khan/RecordRTC#license|MIT}
 * @author {@link http://www.MuazKhan.com|Muaz Khan}
 * @typedef RecordRTCPromisesHandler
 * @class
 * @example
 * var recorder = new RecordRTCPromisesHandler(mediaStream, options);
 * recorder.startRecording()
 *         .then(successCB)
 *         .catch(errorCB);
 * @see {@link https://github.com/muaz-khan/RecordRTC|RecordRTC Source Code}
 * @param {MediaStream} mediaStream - Single media-stream object, array of media-streams, html-canvas-element, etc.
 * @param {object} config - {type:"video", recorderType: MediaStreamRecorder, disableLogs: true, numberOfAudioChannels: 1, bufferSize: 0, sampleRate: 0, video: HTMLVideoElement, etc.}
 * @throws Will throw an error if "new" keyword is not used to initiate "RecordRTCPromisesHandler". Also throws error if first argument "MediaStream" is missing.
 * @requires {@link RecordRTC}
 */

function RecordRTCPromisesHandler(mediaStream, options) {
    if (!this) {
        throw 'Use "new RecordRTCPromisesHandler()"';
    }

    if (typeof mediaStream === 'undefined') {
        throw 'First argument "MediaStream" is required.';
    }

    var self = this;

    /**
     * @property {Blob} blob - Access/reach the native {@link RecordRTC} object.
     * @memberof RecordRTCPromisesHandler
     * @example
     * var internal = recorder.recordRTC.getInternalRecorder();
     * alert(internal instanceof MediaStreamRecorder);
     */
    self.recordRTC = new RecordRTC(mediaStream, options);

    /**
     * This method records MediaStream.
     * @method
     * @memberof RecordRTCPromisesHandler
     * @example
     * recorder.startRecording()
     *         .then(successCB)
     *         .catch(errorCB);
     */
    this.startRecording = function() {
        return new Promise(function(resolve, reject) {
            try {
                self.recordRTC.startRecording();
                resolve();
            } catch (e) {
                reject(e);
            }
        });
    };

    /**
     * This method stops the recording.
     * @method
     * @memberof RecordRTCPromisesHandler
     * @example
     * recorder.stopRecording().then(function() {
     *     var blob = recorder.getBlob();
     * }).catch(errorCB);
     */
    this.stopRecording = function() {
        return new Promise(function(resolve, reject) {
            try {
                self.recordRTC.stopRecording(function(url) {
                    self.blob = self.recordRTC.getBlob();
                    resolve(url);
                });
            } catch (e) {
                reject(e);
            }
        });
    };

    /**
     * This method returns data-url for the recorded blob.
     * @method
     * @memberof RecordRTCPromisesHandler
     * @example
     * recorder.stopRecording().then(function() {
     *     recorder.getDataURL().then(function(dataURL) {
     *         window.open(dataURL);
     *     }).catch(errorCB);;
     * }).catch(errorCB);
     */
    this.getDataURL = function(callback) {
        return new Promise(function(resolve, reject) {
            try {
                self.recordRTC.getDataURL(function(dataURL) {
                    resolve(dataURL);
                });
            } catch (e) {
                reject(e);
            }
        });
    };

    /**
     * This method returns the recorded blob.
     * @method
     * @memberof RecordRTCPromisesHandler
     * @example
     * recorder.stopRecording().then(function() {
     *     var blob = recorder.getBlob();
     * }).catch(errorCB);
     */
    this.getBlob = function() {
        return self.recordRTC.getBlob();
    };

    /**
     * @property {Blob} blob - Recorded data as "Blob" object.
     * @memberof RecordRTCPromisesHandler
     * @example
     * recorder.stopRecording().then(function() {
     *     var blob = recorder.getBlob();
     * }).catch(errorCB);
     */
    this.blob = null;
}

if (typeof RecordRTC !== 'undefined') {
    RecordRTC.RecordRTCPromisesHandler = RecordRTCPromisesHandler;
}