third_party/WebKit/PerformanceTests/Canvas/draw-video-to-hw-accelerated-canvas-2d.html

   1 <!DOCTYPE html>
   2 <html>
   3 <body>
   4 <video id="video" loop></video>
   5 <script src="../resources/runner.js"></script>
   6 <script src="resources/canvas_runner.js"></script>
   7 <script>
   8 var videoElement = document.getElementById("video");
   9 var destCanvas2D = document.createElement("canvas");
  10 var destCtx2D = destCanvas2D.getContext("2d");
  11
  12 function setSize(width, height) {
  13     destCanvas2D.width = width;
  14     destCanvas2D.height = height;
  15 }
  16
  17 function addPlayCallback(videoElement) {
  18     // This logic makes sure this perf test starts after playing the video.
  19     videoElement.addEventListener("canplaythrough", startVideo, true);
  20     videoElement.addEventListener("play", startPerfTest, true);
  21     videoElement.addEventListener('error', function(ev) {
  22         CanvasRunner.logFatalError("\nmp4 codec is not supported on this platform. Received error event:" + ev.target.error.code + "\n");
  23     }, false);
  24     videoElement.src = "../resources/bear-1280x720.mp4";
  25 }
  26
  27 function startVideo() {
  28     // loop can emit this event again.
  29     videoElement.removeEventListener("canplaythrough", startVideo, true);
  30     videoElement.play();
  31 }
  32
  33 function startPerfTest() {
  34     CanvasRunner.start({
  35         description: "This bench test checks the speed on drawing Video element to HW accelerated Canvas2D(1024x1024).",
  36         doRun: doRun,
  37         ensureComplete: ensureComplete});
  38 }
  39
  40 function doRun() {
  41     // draw Video
  42     destCtx2D.drawImage(videoElement, 0, 0);
  43 }
  44
  45 function ensureComplete() {
  46     // Calling getImageData() is just to flush out the content when
  47     // accelerated 2D canvas is in use. The cost of reading 1x1 pixels is low.
  48     destCtx2D.getImageData(0, 0, 1, 1);
  49 }
  50
  51 window.onload = function () {
  52     // It should use setMinimumAccelerated2dCanvasSize() to enable accelerated Canvas for a specified size
  53     // but this API is not available in JS or WebPage. Assume the threshold size is 256x257
  54     // and the dest canvas is HW accelerated Canvas when setting its size to 1024x1024.
  55     setSize(1024, 1024);
  56     addPlayCallback(videoElement);
  57 }
  58
  59 </script>
  60 </body>
  61 </html>