video-canvas-alpha.html | Explore in Territory

<html>
 <head>

  <script>
    if (window.testRunner) {
      testRunner.waitUntilDone();
    }

    function onLoad() {
      video = document.getElementsByTagName('video')[0];
      video.src = "content/test.ogv";

      canvas = document.getElementsByTagName('canvas')[0];
      ctx = canvas.getContext('2d');

      video.load();
      video.addEventListener("canplay", function (e) {
        ctx.globalAlpha = 0.5;
        ctx.drawImage(video, 0, 0);

        if (window.testRunner) {
          testRunner.notifyDone();
        }
      });
    }
  </script>
 </head>
 <body onload="onLoad();">
   <video preload="auto"></video><canvas width="320px" height="240px" style="position:relative;left:-100px;"> </canvas>
 </body>
</html>

chromium/third_party/blink/web_tests/media/video-canvas-alpha.html