title: Dynamic video thumbnail on hover
body: <p>I'm creating a video player with HTML5 and Javascript and I'm wondering if anyone has solved the challenge of creating dynamic thumbnails.</p>
  
  <p>Mimicking youtube video player where you hover over progress bar and a popup shows with a thumbnail. I know that youtube saves out an image and repositions the sprite in the thumbnail viewer frame based on position hovered over.</p>
  
  <p>Is this viable to do with JS and canvas? </p>
  
  <p>What I'm doing now is... hovering over my progress bar creates a copy of the video element. I then set the currentTime on the copied element. I then grab a snapshot using canvas. I'm not sure why, but the images seem to be blank. </p>
  
  <p>Maybe someone has run into this problem?</p>