cleaned up & added README

README.md

@@ -0,0 +1,52 @@
+# WavEncoder #
+
+A fast cross-browser riff wave encoder for real-time audio synthesis in HTML5.
+Works in Web Workers and in the main window
+(in contrast to encoders using window.btoa).
+
+## Examples ##
+
+To play 1 sec of noise in the main window, we can
+
+    <script type='text/javascript' src='safety.js'></script>
+    <script type='text/javascript' src='wavencoder.js'></script>
+    <script type='text/javascript'>
+
+      var samples = [];
+      for (var t = 0; t < 22050; ++t) {
+        samples[t] = 2 * Math.random() - 1;  // in the interval [-1,1]
+      }
+
+      var datauri = WavEncoder.encode(samples);
+      var audio = new Audio(datauri);
+
+      document.onload(function(){ audio.play(); });
+
+    </script>
+
+WavEncoder objects are optimized to create many samples of the same length.
+A typical use case is to generate a set of tones, say in a web worker
+
+    includeScripts('workersafety.js');
+    includeScripts('wavencoder.js');
+
+    var sampleRateHz = 44100;
+    var numSamples = 1 * sampleRateHz;                 // 1 sec
+    var baseFreq = 2 * Math.PI * 27.5 / sampleRateHz;  // A0
+
+    var wavEncoder = new WavEncoder(numSamples, {sampleRateHz: sampleRateHz});
+
+    var tones = [];
+    var samples = [];
+    for (var n = 0; n < 88; ++n) {
+
+      var freq = baseFreq * Math.pow(2, n/12);
+      for (var t = 0; t < numSamples; ++t) {
+        samples[t] = Math.sin(freq * t);
+      }
+
+      tones[n] = wavEncoder.encode(samples);
+    }
+
+    postMessage(tones);
+

safety.js

@@ -13,16 +13,6 @@
 var globalEval = eval;
 'use strict';
 
-var TodoException = function (message) {
-  this.message = message || '(unfinished code)';
-};
-TodoException.prototype.toString = function () {
-  return 'TODO: ' + this.message;
-};
-var TODO = function (message) {
-  throw new TodoException(message);
-};
-
 var AssertException = function (message) {
   this.message = message || '(unspecified)';
 };

workersafety.js

@@ -13,16 +13,6 @@
 var globalEval = eval;
 'use strict';
 
-var TodoException = function (message) {
-  this.message = message || '(unfinished code)';
-};
-TodoException.prototype.toString = function () {
-  return 'TODO: ' + this.message;
-};
-var TODO = function (message) {
-  throw new TodoException(message);
-};
-
 var AssertException = function (message) {
   this.message = message || '(unspecified)';
 };