title: "The canvas has been tainted by cross-origin data" error on Android (no error on desktop)
body: <p>I'm trying to load an image from a video file, draw it on a canvas, and modify canvas pixels. I'm hosting this on a local web server, and it works fine on any desktop computer in my local network. However when I try to open the same page on Android Nexus 7 tablet (also on the local network) I get this error:</p>
  
  <blockquote>
    <p>Failed to execute 'getImageData' on 'CanvasRenderingContext2D': The
    canvas has been tainted by cross-origin data.</p>
  </blockquote>
  
  <p>Here's my final test code:</p>
  
  <pre><code>&lt;!DOCTYPE html&gt;
  &lt;html&gt;
  &lt;body&gt;
  &lt;canvas id="mainCanvas" width="1024" height="576" style = "border:1px solid #d3d3d3;"&gt;
  Your browser does not support the HTML5 canvas tag.
  &lt;/canvas&gt;
  &lt;video id="myVideo" width="0" height="0" &gt;
     &lt;source src="video.mp4" type='video/mp4' crossOrigin="anonymous"&gt;
  &lt;/video&gt;
  &lt;script&gt;
     window.onload = function() {
        var objectImage = document.getElementById('myVideo');
        objectImage.crossOrigin = "Anonymous";
        objectImage.onloadeddata = function() {
           var canvas = document.getElementById("mainCanvas");
           var ctx = canvas.getContext("2d");
           canvas.addEventListener('click', function(event) {
              objectImage.play();
              setTimeout(function() {
                 ctx.drawImage(objectImage, 0, 0);
                 var width = objectImage.videoWidth;
                 var height = objectImage.videoHeight;
  
                 var imageData = ctx.getImageData(0, 0, width, height);
                 var pixels = imageData.data;
                 for (var i = 0; i &lt; pixels.length; i = i + 4) pixels[i] = 0;
                 ctx.putImageData(imageData, 0, 0, 0, 0, width, height);
              }, 3000);
           });
        }
     }
  &lt;/script&gt;
  &lt;/body&gt;
  &lt;/html&gt;
  </code></pre>
  
  <p>As you can see my video file is on the same domain as the rest of the code, and I'm not running this HTML as file:// but as http:// from a web server. I can see the unmodified frame on the screen, just before it calls getImageData(), so I assume video playback worked fine.</p>
  
  <p>I also tried drawing image files on the canvas instead of video, and in this case it seems to work fine, and I can call getImageData without a problem.</p>
  
  <p>Does anyone have a working example of getImageData() after drawing a frame from a video file?</p>