(function() { var onDOMContentLoaded = function() { window.AudioContext = window.AudioContext || window.webkitAudioContext; try { // Create the instance of AudioContext var context = new AudioContext(); } catch (error) { window.alert(error.message + ' : Please use Chrome or Safari.'); return; } // for the instance of AudioBufferSourceNode var source = null; // for legacy browsers context.createGain = context.createGain || context.createGainNode; // Create the instance of GainNode (for Master Volume) var gain = context.createGain(); // Flanger // Create the instance of OscillatorNode (for LFO) var lfo = context.createOscillator(); // for leagcy browsers lfo.start = lfo.start || lfo.noteOn; lfo.stop = lfo.stop || lfo.noteOff; // for legacy browsers context.createDelay = context.createDelay || context.createDelayNode; // for Flanger parameters var delay = context.createDelay(); var depthRate = 0; // This value must be less than or equal to 1.0 (100%) var depth = context.createGain(); var rate = lfo.frequency; var mix = context.createGain(); var feedback = context.createGain(); // Initialize parameters for Flanger delay.delayTime.value = document.getElementById('range-flanger-delay-time').valueAsNumber / 1000; depthRate = document.getElementById('range-flanger-depth').valueAsNumber / 100; depth.gain.value = delay.delayTime.value * depthRate; rate.value = document.getElementById('range-flanger-rate').valueAsNumber; mix.gain.value = document.getElementById('range-flanger-mix').valueAsNumber; feedback.gain.value = document.getElementById('range-flanger-feedback').valueAsNumber; // Trigger 'ended' event var trigger = function() { var event = document.createEvent('Event'); event.initEvent('ended', true, true); if (source instanceof AudioBufferSourceNode) { source.dispatchEvent(event); } }; // This funciton is executed after getting ArrayBuffer of audio data var startAudio = function(arrayBuffer) { // The 2nd argument for decodeAudioData var successCallback = function(audioBuffer) { // The 1st argument (audioBuffer) is the instance of AudioBuffer // If there is previous AudioBufferSourceNode, program stops previous audio if ((source instanceof AudioBufferSourceNode) && (source.buffer instanceof AudioBuffer)) { // Execute onended event handler trigger(); source = null; } // Create the instance of AudioBufferSourceNode source = context.createBufferSource(); // for legacy browsers source.start = source.start || source.noteOn; source.stop = source.stop || source.noteOff; // Set the instance of AudioBuffer source.buffer = audioBuffer; // Set parameters source.playbackRate.value = document.getElementById('range-playback-rate').valueAsNumber; source.loop = document.querySelector('[type="checkbox"]').checked; // GainNode (Master Volume) -> AudioDestinationNode (Output); gain.connect(context.destination); // Connect nodes for original audio // AudioBufferSourceNode (Input) -> GainNode (Master Volume) (-> AudioDestinationNode (Output)) source.connect(gain); // Connect nodes for effect (Flanger) sound // AudioBufferSourceNode (Input) -> DelayNode (Delay) -> GainNode (Mix) -> GainNode (Master Volume) (-> AudioDestinationNode (Output)) source.connect(delay); delay.connect(mix); mix.connect(gain); // Connect nodes for LFO that changes Delay Time periodically // OscillatorNode (LFO) -> GainNode (Depth) -> delayTime (AudioParam) lfo.connect(depth); depth.connect(delay.delayTime); // Connect nodes for Feedback // (AudioBufferSourceNode (Input) ->) DelayNode (Delay) -> GainNode (Feedback) -> DelayNode (Delay) -> ... delay.connect(feedback); feedback.connect(delay); // Start audio source.start(0); // Start LFO lfo.start(0); // Set Callback source.onended = function(event) { // Remove event handler source.onended = null; document.onkeydown = null; // Stop audio source.stop(0); // Stop LFO var type = lfo.type; var frequency = lfo.frequency.value; var detune = lfo.detune.value; lfo.stop(0); // for next start lfo = context.createOscillator(); // for leagcy browsers lfo.start = lfo.start || lfo.noteOn; lfo.stop = lfo.stop || lfo.noteOff; // Set parametres lfo.type = type; lfo.frequency.value = frequency; lfo.detune.value = detune; // Change reference rate = lfo.frequency; console.log('STOP by "on' + event.type + '" event handler !!'); // Audio is not started !! // It is necessary to create the instance of AudioBufferSourceNode again // Cannot replay // source.start(0); }; // Stop audio document.onkeydown = function(event) { // Space ? if (event.keyCode !== 32) { return; } // Execute onended event handler trigger(); return false; }; }; // The 3rd argument for decodeAudioData var errorCallback = function(error) { if (error instanceof Error) { window.alert(error.message); } else { window.alert('Error : "decodeAudioData" method.'); } }; // Create the instance of AudioBuffer (Asynchronously) context.decodeAudioData(arrayBuffer, successCallback, errorCallback); }; /* * File Uploader */ document.getElementById('file-upload-audio').addEventListener('change', function(event) { var uploader = this; var progressArea = document.getElementById('progress-file-upload-audio'); // Get the instance of File (extends Blob) var file = event.target.files[0]; if (!(file instanceof File)) { window.alert('Please upload file.'); } else if (file.type.indexOf('audio') === -1) { window.alert('Please upload audio file.'); } else { // Create the instance of FileReader var reader = new FileReader(); reader.onprogress = function(event) { if (event.lengthComputable && (event.total > 0)) { var rate = Math.floor((event.loaded / event.total) * 100); progressArea.textContent = rate + ' %'; } }; reader.onerror = function() { window.alert('FileReader Error : Error code is ' + reader.error.code); uploader.value = ''; }; // Success read reader.onload = function() { var arrayBuffer = reader.result; // Get ArrayBuffer startAudio(arrayBuffer); uploader.value = ''; progressArea.textContent = file.name; }; // Read the instance of File reader.readAsArrayBuffer(file); } }, false); // Control Master Volume document.getElementById('range-volume').addEventListener('input', function() { var min = gain.gain.minValue || 0; var max = gain.gain.maxValue || 1; if ((this.valueAsNumber >= min) && (this.valueAsNumber <= max)) { gain.gain.value = this.valueAsNumber; document.getElementById('output-volume').textContent = this.value; } }, false); // Control playbackRate document.getElementById('range-playback-rate').addEventListener('input', function() { if (source instanceof AudioBufferSourceNode) { var min = source.playbackRate.minValue || 0; var max = source.playbackRate.maxValue || 1024; if ((this.valueAsNumber >= min) && (this.valueAsNumber <= max)) { source.playbackRate.value = this.valueAsNumber; } } document.getElementById('output-playback-rate').textContent = this.value; }, false); // Toggle loop document.querySelector('[type="checkbox"]').addEventListener(EventWrapper.CLICK, function() { if (source instanceof AudioBufferSourceNode) { source.loop = this.checked; } }, false); // Control delayTime document.getElementById('range-flanger-delay-time').addEventListener('input', function() { delay.delayTime.value = this.valueAsNumber / 1000; depth.gain.value = delay.delayTime.value * depthRate; document.getElementById('output-flanger-delay-time').textContent = this.value; }, false); // Control Flanger Depth document.getElementById('range-flanger-depth').addEventListener('input', function() { depth.gain.value = delay.delayTime.value * (this.valueAsNumber / 100); depthRate = this.valueAsNumber / 100; document.getElementById('output-flanger-depth').textContent = this.value; }, false); // Control Flanger Rate document.getElementById('range-flanger-rate').addEventListener('input', function() { rate.value = this.valueAsNumber; document.getElementById('output-flanger-rate').textContent = this.value; }, false); // Control Flanger Mix document.getElementById('range-flanger-mix').addEventListener('input', function() { var min = mix.gain.minValue || 0; var max = mix.gain.maxValue || 1; if ((this.valueAsNumber >= min) && (this.valueAsNumber <= max)) { mix.gain.value = this.valueAsNumber; document.getElementById('output-flanger-mix').textContent = this.value; } }, false); // Control Flanger Feedback document.getElementById('range-flanger-feedback').addEventListener('input', function() { var min = feedback.gain.minValue || 0; var max = feedback.gain.maxValue || 1; if ((this.valueAsNumber >= min) && (this.valueAsNumber <= max)) { feedback.gain.value = this.valueAsNumber; document.getElementById('output-flanger-feedback').textContent = this.value; } }, false); }; if ((document.readyState === 'interactive') || (document.readyState === 'complete')) { onDOMContentLoaded(); } else { document.addEventListener('DOMContentLoaded', onDOMContentLoaded, true); } })();
function EventWrapper(){ } (function(){ var click = ''; var start = ''; var move = ''; var end = ''; // Touch Panel ? if (/iPhone|iPad|iPod|Android/.test(navigator.userAgent)) { click = 'click'; start = 'touchstart'; move = 'touchmove'; end = 'touchend'; } else { click = 'click'; start = 'mousedown'; move = 'mousemove'; end = 'mouseup'; } EventWrapper.CLICK = click; EventWrapper.START = start; EventWrapper.MOVE = move; EventWrapper.END = end; })();