title: HTML 5 canvas getImageData from an externally-loaded image
body: <p>I know it is not possible to do it straightaway due to security reasons. However, I have heard there are some image-hosting websites that allow their images to be used in a similar manner (Google Picasa?). I could be all wrong, but I would like to know if this is true and if so, how can I get image data from such an image.</p>
  
  <p>Thank you in advance.</p>