wavesurfer.js
Version:
Interactive navigable audio visualization using Web Audio and Canvas
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JavaScript
/*!
* wavesurfer.js 2.0.5 (Sun Mar 04 2018 20:09:58 GMT+0100 (CET))
* https://github.com/katspaugh/wavesurfer.js
* @license BSD-3-Clause
*/
(function webpackUniversalModuleDefinition(root, factory) {
if(typeof exports === 'object' && typeof module === 'object')
module.exports = factory();
else if(typeof define === 'function' && define.amd)
define("spectrogram", [], factory);
else if(typeof exports === 'object')
exports["spectrogram"] = factory();
else
root["WaveSurfer"] = root["WaveSurfer"] || {}, root["WaveSurfer"]["spectrogram"] = factory();
})(typeof self !== 'undefined' ? self : this, function() {
return /******/ (function(modules) { // webpackBootstrap
/******/ // The module cache
/******/ var installedModules = {};
/******/
/******/ // The require function
/******/ function __webpack_require__(moduleId) {
/******/
/******/ // Check if module is in cache
/******/ if(installedModules[moduleId]) {
/******/ return installedModules[moduleId].exports;
/******/ }
/******/ // Create a new module (and put it into the cache)
/******/ var module = installedModules[moduleId] = {
/******/ i: moduleId,
/******/ l: false,
/******/ exports: {}
/******/ };
/******/
/******/ // Execute the module function
/******/ modules[moduleId].call(module.exports, module, module.exports, __webpack_require__);
/******/
/******/ // Flag the module as loaded
/******/ module.l = true;
/******/
/******/ // Return the exports of the module
/******/ return module.exports;
/******/ }
/******/
/******/
/******/ // expose the modules object (__webpack_modules__)
/******/ __webpack_require__.m = modules;
/******/
/******/ // expose the module cache
/******/ __webpack_require__.c = installedModules;
/******/
/******/ // define getter function for harmony exports
/******/ __webpack_require__.d = function(exports, name, getter) {
/******/ if(!__webpack_require__.o(exports, name)) {
/******/ Object.defineProperty(exports, name, {
/******/ configurable: false,
/******/ enumerable: true,
/******/ get: getter
/******/ });
/******/ }
/******/ };
/******/
/******/ // getDefaultExport function for compatibility with non-harmony modules
/******/ __webpack_require__.n = function(module) {
/******/ var getter = module && module.__esModule ?
/******/ function getDefault() { return module['default']; } :
/******/ function getModuleExports() { return module; };
/******/ __webpack_require__.d(getter, 'a', getter);
/******/ return getter;
/******/ };
/******/
/******/ // Object.prototype.hasOwnProperty.call
/******/ __webpack_require__.o = function(object, property) { return Object.prototype.hasOwnProperty.call(object, property); };
/******/
/******/ // __webpack_public_path__
/******/ __webpack_require__.p = "localhost:8080/dist/plugin/";
/******/
/******/ // Load entry module and return exports
/******/ return __webpack_require__(__webpack_require__.s = 3);
/******/ })
/************************************************************************/
/******/ ({
/***/ 3:
/***/ (function(module, exports, __webpack_require__) {
"use strict";
Object.defineProperty(exports, "__esModule", {
value: true
});
var _createClass = function () { function defineProperties(target, props) { for (var i = 0; i < props.length; i++) { var descriptor = props[i]; descriptor.enumerable = descriptor.enumerable || false; descriptor.configurable = true; if ("value" in descriptor) descriptor.writable = true; Object.defineProperty(target, descriptor.key, descriptor); } } return function (Constructor, protoProps, staticProps) { if (protoProps) defineProperties(Constructor.prototype, protoProps); if (staticProps) defineProperties(Constructor, staticProps); return Constructor; }; }();
function _classCallCheck(instance, Constructor) { if (!(instance instanceof Constructor)) { throw new TypeError("Cannot call a class as a function"); } }
/**
* Calculate FFT - Based on https://github.com/corbanbrook/dsp.js
*/
/* eslint-disable complexity, no-redeclare, no-var, one-var */
var FFT = function FFT(bufferSize, sampleRate, windowFunc, alpha) {
this.bufferSize = bufferSize;
this.sampleRate = sampleRate;
this.bandwidth = 2 / bufferSize * sampleRate / 2;
this.sinTable = new Float32Array(bufferSize);
this.cosTable = new Float32Array(bufferSize);
this.windowValues = new Float32Array(bufferSize);
this.reverseTable = new Uint32Array(bufferSize);
this.peakBand = 0;
this.peak = 0;
switch (windowFunc) {
case 'bartlett':
for (var i = 0; i < bufferSize; i++) {
this.windowValues[i] = 2 / (bufferSize - 1) * ((bufferSize - 1) / 2 - Math.abs(i - (bufferSize - 1) / 2));
}
break;
case 'bartlettHann':
for (var i = 0; i < bufferSize; i++) {
this.windowValues[i] = 0.62 - 0.48 * Math.abs(i / (bufferSize - 1) - 0.5) - 0.38 * Math.cos(Math.PI * 2 * i / (bufferSize - 1));
}
break;
case 'blackman':
alpha = alpha || 0.16;
for (var i = 0; i < bufferSize; i++) {
this.windowValues[i] = (1 - alpha) / 2 - 0.5 * Math.cos(Math.PI * 2 * i / (bufferSize - 1)) + alpha / 2 * Math.cos(4 * Math.PI * i / (bufferSize - 1));
}
break;
case 'cosine':
for (var i = 0; i < bufferSize; i++) {
this.windowValues[i] = Math.cos(Math.PI * i / (bufferSize - 1) - Math.PI / 2);
}
break;
case 'gauss':
alpha = alpha || 0.25;
for (var i = 0; i < bufferSize; i++) {
this.windowValues[i] = Math.pow(Math.E, -0.5 * Math.pow((i - (bufferSize - 1) / 2) / (alpha * (bufferSize - 1) / 2), 2));
}
break;
case 'hamming':
for (var i = 0; i < bufferSize; i++) {
this.windowValues[i] = 0.54 - 0.46 * Math.cos(Math.PI * 2 * i / (bufferSize - 1));
}
break;
case 'hann':
case undefined:
for (var i = 0; i < bufferSize; i++) {
this.windowValues[i] = 0.5 * (1 - Math.cos(Math.PI * 2 * i / (bufferSize - 1)));
}
break;
case 'lanczoz':
for (var i = 0; i < bufferSize; i++) {
this.windowValues[i] = Math.sin(Math.PI * (2 * i / (bufferSize - 1) - 1)) / (Math.PI * (2 * i / (bufferSize - 1) - 1));
}
break;
case 'rectangular':
for (var i = 0; i < bufferSize; i++) {
this.windowValues[i] = 1;
}
break;
case 'triangular':
for (var i = 0; i < bufferSize; i++) {
this.windowValues[i] = 2 / bufferSize * (bufferSize / 2 - Math.abs(i - (bufferSize - 1) / 2));
}
break;
default:
throw Error("No such window function '" + windowFunc + "'");
}
var limit = 1;
var bit = bufferSize >> 1;
var i;
while (limit < bufferSize) {
for (i = 0; i < limit; i++) {
this.reverseTable[i + limit] = this.reverseTable[i] + bit;
}
limit = limit << 1;
bit = bit >> 1;
}
for (i = 0; i < bufferSize; i++) {
this.sinTable[i] = Math.sin(-Math.PI / i);
this.cosTable[i] = Math.cos(-Math.PI / i);
}
this.calculateSpectrum = function (buffer) {
// Locally scope variables for speed up
var bufferSize = this.bufferSize,
cosTable = this.cosTable,
sinTable = this.sinTable,
reverseTable = this.reverseTable,
real = new Float32Array(bufferSize),
imag = new Float32Array(bufferSize),
bSi = 2 / this.bufferSize,
sqrt = Math.sqrt,
rval,
ival,
mag,
spectrum = new Float32Array(bufferSize / 2);
var k = Math.floor(Math.log(bufferSize) / Math.LN2);
if (Math.pow(2, k) !== bufferSize) {
throw 'Invalid buffer size, must be a power of 2.';
}
if (bufferSize !== buffer.length) {
throw 'Supplied buffer is not the same size as defined FFT. FFT Size: ' + bufferSize + ' Buffer Size: ' + buffer.length;
}
var halfSize = 1,
phaseShiftStepReal,
phaseShiftStepImag,
currentPhaseShiftReal,
currentPhaseShiftImag,
off,
tr,
ti,
tmpReal;
for (var i = 0; i < bufferSize; i++) {
real[i] = buffer[reverseTable[i]] * this.windowValues[reverseTable[i]];
imag[i] = 0;
}
while (halfSize < bufferSize) {
phaseShiftStepReal = cosTable[halfSize];
phaseShiftStepImag = sinTable[halfSize];
currentPhaseShiftReal = 1;
currentPhaseShiftImag = 0;
for (var fftStep = 0; fftStep < halfSize; fftStep++) {
var i = fftStep;
while (i < bufferSize) {
off = i + halfSize;
tr = currentPhaseShiftReal * real[off] - currentPhaseShiftImag * imag[off];
ti = currentPhaseShiftReal * imag[off] + currentPhaseShiftImag * real[off];
real[off] = real[i] - tr;
imag[off] = imag[i] - ti;
real[i] += tr;
imag[i] += ti;
i += halfSize << 1;
}
tmpReal = currentPhaseShiftReal;
currentPhaseShiftReal = tmpReal * phaseShiftStepReal - currentPhaseShiftImag * phaseShiftStepImag;
currentPhaseShiftImag = tmpReal * phaseShiftStepImag + currentPhaseShiftImag * phaseShiftStepReal;
}
halfSize = halfSize << 1;
}
for (var i = 0, N = bufferSize / 2; i < N; i++) {
rval = real[i];
ival = imag[i];
mag = bSi * sqrt(rval * rval + ival * ival);
if (mag > this.peak) {
this.peakBand = i;
this.peak = mag;
}
spectrum[i] = mag;
}
return spectrum;
};
};
/* eslint-enable complexity, no-redeclare, no-var, one-var */
/**
* @typedef {Object} SpectrogramPluginParams
* @property {string|HTMLElement} container Selector of element or element in
* which to render
* @property {number} fftSamples=512 number of samples to fetch to FFT. Must be
* a pwer of 2.
* @property {number} noverlap Size of the overlapping window. Must be <
* fftSamples. Auto deduced from canvas size by default.
* @property {string} windowFunc='hann' The window function to be used. One of
* these: `'bartlett'`, `'bartlettHann'`, `'blackman'`, `'cosine'`, `'gauss'`,
* `'hamming'`, `'hann'`, `'lanczoz'`, `'rectangular'`, `'triangular'`
* @property {?number} alpha Some window functions have this extra value.
* (Between 0 and 1)
* @property {number} pixelRatio=wavesurfer.params.pixelRatio to control the
* size of the spectrogram in relation with its canvas. 1 = Draw on the whole
* canvas. 2 = Draw on a quarter (1/2 the length and 1/2 the width)
* @property {?boolean} deferInit Set to true to manually call
* `initPlugin('spectrogram')`
*/
/**
* Render a spectrogram visualisation of the audio.
*
* @implements {PluginClass}
* @extends {Observer}
* @example
* // es6
* import SpectrogramPlugin from 'wavesurfer.spectrogram.js';
*
* // commonjs
* var SpectrogramPlugin = require('wavesurfer.spectrogram.js');
*
* // if you are using <script> tags
* var SpectrogramPlugin = window.WaveSurfer.spectrogram;
*
* // ... initialising wavesurfer with the plugin
* var wavesurfer = WaveSurfer.create({
* // wavesurfer options ...
* plugins: [
* SpectrogramPlugin.create({
* // plugin options ...
* })
* ]
* });
*/
var SpectrogramPlugin = function () {
_createClass(SpectrogramPlugin, null, [{
key: 'create',
/**
* Spectrogram plugin definition factory
*
* This function must be used to create a plugin definition which can be
* used by wavesurfer to correctly instantiate the plugin.
*
* @param {SpectrogramPluginParams} params parameters use to initialise the plugin
* @return {PluginDefinition} an object representing the plugin
*/
value: function create(params) {
return {
name: 'spectrogram',
deferInit: params && params.deferInit ? params.deferInit : false,
params: params,
staticProps: {
FFT: FFT
},
instance: SpectrogramPlugin
};
}
}]);
function SpectrogramPlugin(params, ws) {
var _this = this;
_classCallCheck(this, SpectrogramPlugin);
this.params = params;
this.wavesurfer = ws;
this.util = ws.util;
this.frequenciesDataUrl = params.frequenciesDataUrl;
this._onScroll = function (e) {
_this.updateScroll(e);
};
this._onReady = function () {
var drawer = _this.drawer = ws.drawer;
_this.container = 'string' == typeof params.container ? document.querySelector(params.container) : params.container;
if (!_this.container) {
throw Error('No container for WaveSurfer spectrogram');
}
_this.width = drawer.width;
_this.pixelRatio = _this.params.pixelRatio || ws.params.pixelRatio;
_this.fftSamples = _this.params.fftSamples || ws.params.fftSamples || 512;
_this.height = _this.fftSamples / 2;
_this.noverlap = params.noverlap;
_this.windowFunc = params.windowFunc;
_this.alpha = params.alpha;
_this.createWrapper();
_this.createCanvas();
_this.render();
drawer.wrapper.addEventListener('scroll', _this._onScroll);
ws.on('redraw', function () {
return _this.render();
});
};
}
_createClass(SpectrogramPlugin, [{
key: 'init',
value: function init() {
// Check if ws is ready
if (this.wavesurfer.isReady) {
this._onReady();
}
this.wavesurfer.on('ready', this._onReady);
}
}, {
key: 'destroy',
value: function destroy() {
this.unAll();
this.wavesurfer.un('ready', this._onReady);
this.drawer.wrapper.removeEventListener('scroll', this._onScroll);
this.wavesurfer = null;
this.util = null;
this.params = null;
if (this.wrapper) {
this.wrapper.parentNode.removeChild(this.wrapper);
this.wrapper = null;
}
}
}, {
key: 'createWrapper',
value: function createWrapper() {
var _this2 = this;
var prevSpectrogram = this.container.querySelector('spectrogram');
if (prevSpectrogram) {
this.container.removeChild(prevSpectrogram);
}
var wsParams = this.wavesurfer.params;
this.wrapper = document.createElement('spectrogram');
// if labels are active
if (this.params.labels) {
var labelsEl = this.labelsEl = document.createElement('canvas');
labelsEl.classList.add('spec-labels');
this.drawer.style(labelsEl, {
left: 0,
position: 'absolute',
zIndex: 9,
height: this.height / this.pixelRatio + 'px',
width: 55 / this.pixelRatio + 'px'
});
this.wrapper.appendChild(labelsEl);
// can be customized in next version
this.loadLabels('rgba(68,68,68,0.5)', '12px', '10px', '', '#fff', '#f7f7f7', 'center', '#specLabels');
}
this.drawer.style(this.wrapper, {
display: 'block',
position: 'relative',
userSelect: 'none',
webkitUserSelect: 'none',
height: this.height / this.pixelRatio + 'px'
});
if (wsParams.fillParent || wsParams.scrollParent) {
this.drawer.style(this.wrapper, {
width: '100%',
overflowX: 'hidden',
overflowY: 'hidden'
});
}
this.container.appendChild(this.wrapper);
this.wrapper.addEventListener('click', function (e) {
e.preventDefault();
var relX = 'offsetX' in e ? e.offsetX : e.layerX;
_this2.fireEvent('click', relX / _this2.scrollWidth || 0);
});
}
}, {
key: 'createCanvas',
value: function createCanvas() {
var canvas = this.canvas = this.wrapper.appendChild(document.createElement('canvas'));
this.spectrCc = canvas.getContext('2d');
this.util.style(canvas, {
position: 'absolute',
zIndex: 4
});
}
}, {
key: 'render',
value: function render() {
this.updateCanvasStyle();
if (this.frequenciesDataUrl) {
this.loadFrequenciesData(this.frequenciesDataUrl);
} else {
this.getFrequencies(this.drawSpectrogram);
}
}
}, {
key: 'updateCanvasStyle',
value: function updateCanvasStyle() {
var width = Math.round(this.width / this.pixelRatio) + 'px';
this.canvas.width = this.width;
this.canvas.height = this.height;
this.canvas.style.width = width;
}
}, {
key: 'drawSpectrogram',
value: function drawSpectrogram(frequenciesData, my) {
var spectrCc = my.spectrCc;
var length = my.wavesurfer.backend.getDuration();
var height = my.height;
var pixels = my.resample(frequenciesData);
var heightFactor = my.buffer ? 2 / my.buffer.numberOfChannels : 1;
var i = void 0;
var j = void 0;
for (i = 0; i < pixels.length; i++) {
for (j = 0; j < pixels[i].length; j++) {
var colorValue = 255 - pixels[i][j];
my.spectrCc.fillStyle = 'rgb(' + colorValue + ', ' + colorValue + ', ' + colorValue + ')';
my.spectrCc.fillRect(i, height - j * heightFactor, 1, heightFactor);
}
}
}
}, {
key: 'getFrequencies',
value: function getFrequencies(callback) {
var fftSamples = this.fftSamples;
var buffer = this.buffer = this.wavesurfer.backend.buffer;
var channelOne = buffer.getChannelData(0);
var bufferLength = buffer.length;
var sampleRate = buffer.sampleRate;
var frequencies = [];
if (!buffer) {
this.fireEvent('error', 'Web Audio buffer is not available');
return;
}
var noverlap = this.noverlap;
if (!noverlap) {
var uniqueSamplesPerPx = buffer.length / this.canvas.width;
noverlap = Math.max(0, Math.round(fftSamples - uniqueSamplesPerPx));
}
var fft = new FFT(fftSamples, sampleRate, this.windowFunc, this.alpha);
var maxSlicesCount = Math.floor(bufferLength / (fftSamples - noverlap));
var currentOffset = 0;
while (currentOffset + fftSamples < channelOne.length) {
var segment = channelOne.slice(currentOffset, currentOffset + fftSamples);
var spectrum = fft.calculateSpectrum(segment);
var array = new Uint8Array(fftSamples / 2);
var j = void 0;
for (j = 0; j < fftSamples / 2; j++) {
array[j] = Math.max(-255, Math.log10(spectrum[j]) * 45);
}
frequencies.push(array);
currentOffset += fftSamples - noverlap;
}
callback(frequencies, this);
}
}, {
key: 'loadFrequenciesData',
value: function loadFrequenciesData(url) {
var _this3 = this;
var ajax = this.util.ajax({ url: url });
ajax.on('success', function (data) {
return _this3.drawSpectrogram(JSON.parse(data), _this3);
});
ajax.on('error', function (e) {
return _this3.fireEvent('error', 'XHR error: ' + e.target.statusText);
});
return ajax;
}
}, {
key: 'freqType',
value: function freqType(freq) {
return freq >= 1000 ? (freq / 1000).toFixed(1) : Math.round(freq);
}
}, {
key: 'unitType',
value: function unitType(freq) {
return freq >= 1000 ? 'KHz' : 'Hz';
}
}, {
key: 'loadLabels',
value: function loadLabels(bgFill, fontSizeFreq, fontSizeUnit, fontType, textColorFreq, textColorUnit, textAlign, container) {
var frequenciesHeight = this.height;
bgFill = bgFill || 'rgba(68,68,68,0)';
fontSizeFreq = fontSizeFreq || '12px';
fontSizeUnit = fontSizeUnit || '10px';
fontType = fontType || 'Helvetica';
textColorFreq = textColorFreq || '#fff';
textColorUnit = textColorUnit || '#fff';
textAlign = textAlign || 'center';
container = container || '#specLabels';
var getMaxY = frequenciesHeight || 512;
var labelIndex = 5 * (getMaxY / 256);
var freqStart = 0;
var step = (this.wavesurfer.backend.ac.sampleRate / 2 - freqStart) / labelIndex;
var ctx = this.labelsEl.getContext('2d');
this.labelsEl.height = this.height;
this.labelsEl.width = 55;
ctx.fillStyle = bgFill;
ctx.fillRect(0, 0, 55, getMaxY);
ctx.fill();
var i = void 0;
for (i = 0; i <= labelIndex; i++) {
ctx.textAlign = textAlign;
ctx.textBaseline = 'middle';
var freq = freqStart + step * i;
var index = Math.round(freq / (this.sampleRate / 2) * this.fftSamples);
var label = this.freqType(freq);
var units = this.unitType(freq);
var x = 16;
var yLabelOffset = 2;
if (i == 0) {
ctx.fillStyle = textColorUnit;
ctx.font = fontSizeUnit + ' ' + fontType;
ctx.fillText(units, x + 24, getMaxY + i - 10);
ctx.fillStyle = textColorFreq;
ctx.font = fontSizeFreq + ' ' + fontType;
ctx.fillText(label, x, getMaxY + i - 10);
} else {
ctx.fillStyle = textColorUnit;
ctx.font = fontSizeUnit + ' ' + fontType;
ctx.fillText(units, x + 24, getMaxY - i * 50 + yLabelOffset);
ctx.fillStyle = textColorFreq;
ctx.font = fontSizeFreq + ' ' + fontType;
ctx.fillText(label, x, getMaxY - i * 50 + yLabelOffset);
}
}
}
}, {
key: 'updateScroll',
value: function updateScroll(e) {
if (this.wrapper) {
this.wrapper.scrollLeft = e.target.scrollLeft;
}
}
}, {
key: 'resample',
value: function resample(oldMatrix) {
var columnsNumber = this.width;
var newMatrix = [];
var oldPiece = 1 / oldMatrix.length;
var newPiece = 1 / columnsNumber;
var i = void 0;
for (i = 0; i < columnsNumber; i++) {
var column = new Array(oldMatrix[0].length);
var j = void 0;
for (j = 0; j < oldMatrix.length; j++) {
var oldStart = j * oldPiece;
var oldEnd = oldStart + oldPiece;
var newStart = i * newPiece;
var newEnd = newStart + newPiece;
var overlap = oldEnd <= newStart || newEnd <= oldStart ? 0 : Math.min(Math.max(oldEnd, newStart), Math.max(newEnd, oldStart)) - Math.max(Math.min(oldEnd, newStart), Math.min(newEnd, oldStart));
var k = void 0;
/* eslint-disable max-depth */
if (overlap > 0) {
for (k = 0; k < oldMatrix[0].length; k++) {
if (column[k] == null) {
column[k] = 0;
}
column[k] += overlap / newPiece * oldMatrix[j][k];
}
}
/* eslint-enable max-depth */
}
var intColumn = new Uint8Array(oldMatrix[0].length);
var m = void 0;
for (m = 0; m < oldMatrix[0].length; m++) {
intColumn[m] = column[m];
}
newMatrix.push(intColumn);
}
return newMatrix;
}
}]);
return SpectrogramPlugin;
}();
exports.default = SpectrogramPlugin;
module.exports = exports['default'];
/***/ })
/******/ });
});
//# sourceMappingURL=wavesurfer.spectrogram.js.map