third_party/WebKit/LayoutTests/webaudio/audioparam-setTargetAtTime.html

   1 <!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN">
   2 <html>
   3 <head>
   4 <script src="resources/compatibility.js"></script>
   5 <script src="resources/audio-testing.js"></script>
   6 <script src="resources/audioparam-testing.js"></script>
   7 <script src="../resources/js-test.js"></script>
   8 </head>
   9
  10 <body>
  11 <div id="description"></div>
  12 <div id="console"></div>
  13
  14 <script>
  15 description("Test AudioParam setTargetAtTime() functionality.");
  16
  17 // Play a long DC signal out through an AudioGainNode, and call setValueAtTime() and
  18 // setTargetAtTime at regular intervals to set the starting value and the target
  19 // value. Each time interval has a ramp with a different starting and target value so that
  20 // there is a discontinuity at each time interval boundary.  The discontinuity is for testing
  21 // timing.  Also, we alternate between an increasing and decreasing ramp for each interval.
  22
  23 // Number of tests to run.
  24 var numberOfTests = 100;
  25
  26 // Max allowed difference between the rendered data and the expected result.
  27 var maxAllowedError = 3.9e-5;
  28
  29 // The AudioGainNode starts with this value instead of the default value.
  30 var initialValue = 100;
  31
  32 // Set the gain node value to the specified value at the specified time.
  33 function setValue(value, time)
  34 {
  35     gainNode.gain.setValueAtTime(value, time);
  36 }
  37
  38 // Generate an exponential approach starting at |startTime| with a target value of |value|.
  39 function automation(value, startTime, endTime)
  40 {
  41     // endTime is not used for setTargetAtTime.
  42     gainNode.gain.setTargetAtTime(value, startTime, timeConstant)
  43 }
  44
  45 function runTest()
  46 {
  47     createAudioGraphAndTest(numberOfTests,
  48                             initialValue,
  49                             setValue,
  50                             automation,
  51                             "setTargetAtTime()",
  52                             maxAllowedError,
  53                             createExponentialApproachArray);
  54 }
  55
  56 runTest();
  57 successfullyParsed = true;
  58
  59 </script>
  60
  61 </body>
  62 </html>