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<!DOCTYPE HTML>
<html>
<!--
https://bugzilla.mozilla.org/show_bug.cgi?id=389366
-->
<head>
  <title>Test for Bug 389366</title>
  <script type="text/javascript" src="/tests/SimpleTest/SimpleTest.js"></script>        
  <link rel="stylesheet" type="text/css" href="/tests/SimpleTest/test.css" />
</head>
<body>
<a target="_blank" href="https://bugzilla.mozilla.org/show_bug.cgi?id=389366">Mozilla Bug 389366</a>
<p id="display"></p>
<div id="content" style="display: none">
  <h4>Canvas testcase</h4>
  
  Canvas, with pixel set to #ff0000 at 50% opacity:<br>
  <canvas id="canvas1" width="10" height="10"></canvas>
  <br>
  <canvas id="canvas2" width="10" height="10"></canvas>
  
</div>
<pre id="test">
<script class="testbody" type="text/javascript">

SimpleTest.waitForExplicitFinish();

function test()
{
  // Draw to canvas1
  var canvas1 = document.getElementById("canvas1");
  var ctx1 = canvas1.getContext("2d");

  ctx1.globalAlpha = 0.502;
  ctx1.fillStyle = "#FF0000";
  ctx1.fillRect(0, 0, 10, 10);

  var data1 = ctx1.getImageData(0,0,1,1).data;
  isDeeply(data1, [255, 0, 0, 128], "expected half-transparent red canvas 1");

  // half-transparent red 10x10 square
  var imgData = ctx1.createImageData(10, 10);
  var rgba = [ 255, 0, 0, 128 ];
  for (i = 0; i < 50; ++i) {
    for (j = 0; j < 4; ++j) {
      imgData.data[(i * 4) + j] = rgba[j];
    }
  }

  var canvas2 = document.getElementById("canvas2");
  var ctx2 = canvas2.getContext("2d");
  ctx2.putImageData(imgData, 0, 0);

  var data2 = ctx2.getImageData(0,0,1,1).data;
  isDeeply(data2, [255, 0, 0, 128], "expected half-transparent red canvas 2");

  SimpleTest.finish();
}

addLoadEvent(test);

</script>
</pre>
</body>
</html>