The Tor Browser: content/media/webaudio/test/test

Incorporate requested changes from Mozilla in review:
https://bugzilla.mozilla.org/show_bug.cgi?id=1123480#c6

     1 <!DOCTYPE HTML>

     2 <html>

     3 <head>

     4   <title>Test repeating audio is not distorted</title>

     5   <script type="text/javascript" src="/tests/SimpleTest/SimpleTest.js"></script>

     6   <script type="text/javascript" src="webaudio.js"></script>

     7   <link rel="stylesheet" type="text/css" href="/tests/SimpleTest/test.css" />

     8 </head>

     9 <body>

    10 <pre id="test">

    11 <script class="testbody" type="text/javascript">

    13 function gcd(a, b) {

    14   if (b === 0) {

    15     return a;

    16   }

    17   return gcd(b, a % b);

    18 }

    20 var SAMPLE_PLACEMENT = 128;

    22 var gTest = {

    23   length: 2048,

    24   numberOfChannels: 1,

    26   createGraph: function(context) {

    27     var freq = Math.round(context.sampleRate / SAMPLE_PLACEMENT);

    28     var dur = context.sampleRate / gcd(freq, context.sampleRate);

    29     var buffer = context.createBuffer(1, dur, context.sampleRate);

    31     for (var i = 0; i < context.sampleRate; ++i) {

    32       buffer.getChannelData(0)[i] = Math.sin(freq * 2 * Math.PI * i / context.sampleRate);

    33     }

    35     var source = context.createBufferSource();

    36     source.buffer = buffer;

    37     source.loop = true;

    38     source.playbackRate.setValueAtTime(0.5, SAMPLE_PLACEMENT / context.sampleRate);

    39     source.start(0);

    41     return source;

    42   },

    44   createExpectedBuffers: function(context) {

    45     var freq = Math.round(context.sampleRate / SAMPLE_PLACEMENT);

    46     var expectedBuffer = context.createBuffer(1, 2048, context.sampleRate);

    47     var c = expectedBuffer.getChannelData(0);

    48     for (var i = 0; i < c.length; ++i) {

    49       if (i < SAMPLE_PLACEMENT) {

    50         c[i] = Math.sin(freq * 2 * Math.PI * i / context.sampleRate);

    51       } else {

    52         c[i] = Math.sin(freq / 2 * 2 * Math.PI * (i + SAMPLE_PLACEMENT) / context.sampleRate);

    53       }

    54     }

    56     return expectedBuffer;

    57   },

    58 };

    60 runTest();

    61 </script>

    62 </pre>

    63 </body>

    64 </html>

The Tor Browser / file revision