1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 100 101 102 103 104 105 106 107 108 109 110 111 112 113 114 115 116 117 118 119 120 121 122 123 124 125 126 127 128 129 130 131 132 133 134 135 136 137 138 139 140 141 142 143 144 145 146 147 148 149 150 151 152 153 154 155 156 157 158 159 160 161 162 163 164 165 166 167 168 169 170 171 172 173 174 175 176 177 178 179 180 181 182 183 184 185 186 187 188 189 190 191 192 193 194 195 196 197 198 199 200 201 202 203 204 205 206 207 208 209 210 211 212 213 214 215 216 217 218 219 220 221 222 223 224 225 226 227 228 229 230 231 232 233 234 235 236 237 238 239 240 241 242 243 244 245 246 247 248 249 250 251 252 253 254 255 256 257 258 259 260 261 262 263 264 265 266 267 268 269 270 | ( 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 var gain = context.createGain(); var drawAudio = function (canvas, data, sampleRate) { var canvasContext = canvas.getContext( '2d' ); var width = canvas.width; var height = canvas.height; var paddingTop = 20; var paddingBottom = 20; var paddingLeft = 30; var paddingRight = 30; var innerWidth = width - paddingLeft - paddingRight; var innerHeight = height - paddingTop - paddingBottom; var innerBottom = height - paddingBottom; // Sampling period var period = 1 / sampleRate; // This value is the number of samples during 50 msec var n50msec = Math.floor(50 * Math.pow(10, -3) * sampleRate); // Clear previous data canvasContext.clearRect(0, 0, width, height); // Draw audio wave canvasContext.beginPath(); for ( var i = 0, len = data.length; i < len; i++) { // 50 msec ? if ((i % n50msec) === 0) { var x = Math.floor((i / len) * innerWidth) + paddingLeft; var y = Math.floor(((1 - data[i]) / 2) * innerHeight) + paddingTop; if (i === 0) { canvasContext.moveTo(x, y); } else { canvasContext.lineTo(x, y); } } } canvasContext.strokeStyle = 'rgba(0, 0, 255, 1.0)' ; canvasContext.lineWidth = 0.5; canvasContext.lineCap = 'round' ; canvasContext.lineJoin = 'miter' ; canvasContext.stroke(); }; // 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 // Get audio binary data for drawing wave var channelLs = new Float32Array(audioBuffer.length); var channelRs = new Float32Array(audioBuffer.length); console.log( 'numberOfChannels : ' + audioBuffer.numberOfChannels); // Stereo ? if (audioBuffer.numberOfChannels > 1) { // Stereo channelLs.set(audioBuffer.getChannelData(0)); channelRs.set(audioBuffer.getChannelData(1)); drawAudio(document.querySelectorAll( 'canvas' )[0], channelLs, audioBuffer.sampleRate); drawAudio(document.querySelectorAll( 'canvas' )[1], channelRs, audioBuffer.sampleRate); } else if (audioBuffer.numberOfChannels > 0) { // Monaural channelLs.set(audioBuffer.getChannelData(0)); drawAudio(document.querySelectorAll( 'canvas' )[0], channelLs, audioBuffer.sampleRate); } else { window.alert( 'The number of channels is invalid.' ); return ; } // 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; // AudioBufferSourceNode (Input) -> GainNode (Volume) -> AudioDestinationNode (Output) source.connect(gain); gain.connect(context.destination); // Start audio source.start(0); // Set Callback source.onended = function (event) { // Remove event handler source.onended = null ; document.onkeydown = null ; // Stop audio source.stop(0); 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 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 ); }; if ((document.readyState === 'interactive' ) || (document.readyState === 'complete' )) { onDOMContentLoaded(); } else { document.addEventListener( 'DOMContentLoaded' , onDOMContentLoaded, true ); } })(); |
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 | 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; })(); |