LayoutTests/webaudio/audioparam-setTargetAtTime.html

   1 <!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN">
   2 <html>
   3 <head>
   4 <script src="resources/audio-testing.js"></script>
   5 <script src="resources/audioparam-testing.js"></script>
   6 <script src="../fast/js/resources/js-test-pre.js"></script>
   7 </head>
   8
   9 <body>
  10 <div id="description"></div>
  11 <div id="console"></div>
  12
  13 <script>
  14 description("Test AudioParam setTargetAtTime() functionality.");
  15
  16 // Play a long DC signal out through an AudioGainNode, and call setValueAtTime() and
  17 // setTargetAtTime at regular intervals to set the starting value and the target
  18 // value. Each time interval has a ramp with a different starting and target value so that
  19 // there is a discontinuity at each time interval boundary.  The discontinuity is for testing
  20 // timing.  Also, we alternate between an increasing and decreasing ramp for each interval.
  21
  22 // Number of tests to run.
  23 var numberOfTests = 100;
  24
  25 // Max allowed difference between the rendered data and the expected result.
  26 var maxAllowedError = 2.79e-5;
  27
  28 // The AudioGainNode starts with this value instead of the default value.
  29 var initialValue = 100;
  30
  31 // Set the gain node value to the specified value at the specified time.
  32 function setValue(value, time)
  33 {
  34     gainNode.gain.setValueAtTime(value, time);
  35 }
  36
  37 // Generate an exponential approach starting at |startTime| with a target value of |value|.
  38 function automation(value, startTime, endTime)
  39 {
  40     // endTime is not used for setTargetAtTime.
  41     gainNode.gain.setTargetAtTime(value, startTime, timeConstant)
  42 }
  43
  44 function runTest()
  45 {
  46     createAudioGraphAndTest(numberOfTests,
  47                             initialValue,
  48                             setValue,
  49                             automation,
  50                             "setTargetAtTime()",
  51                             maxAllowedError,
  52                             createExponentialApproachArray);
  53 }
  54
  55 runTest();
  56 successfullyParsed = true;
  57
  58 </script>
  59
  60 <script src="../fast/js/resources/js-test-post.js"></script>
  61 </body>
  62 </html>