video-canvas.html

<!DOCTYPE html>
<html lang="en">
<head>
<meta charset="utf-8" />
<title>Dizzy</title>
<style>
* { margin: 0;}
body { font-family: helvetica; padding: 10px;  }
input { width: 50px; }
/*video, canvas { display: block; }*/
p { margin-top: 20px;}
</style>
</head>
<body>
  <video height="360" width="480">
    <source src="assets/dizzy.mp4" />
    <source src="assets/dizzy.ogv" />
  </video><canvas></canvas>
  <p>
    <input type="button" id="play" value="play">
    <span id="position">00:00</span> / <span id="duration"></span>
  </p>
<script src="/js/h5utils.js"></script>
<script>
var video = document.querySelector('video');
var togglePlay = document.querySelector('#play');
var position = document.querySelector('#position');
var canvas = document.querySelector('canvas');
var ctx = canvas.getContext('2d');

addEvent(togglePlay, 'click', function () {
  video.playbackRate = 0.5;
  if (video.paused) {
    if (video.ended) video.currentTime = 0;
    video.play();
    this.value = "pause";
  } else {
    video.pause();
    this.value = "play";
  }
});

setInterval(function () {
  position.innerHTML = asTime(video.currentTime);

  // ctx.restore();
  ctx.drawImage(video, 0, 0, video.width, video.height, 0, 0, canvas.width, canvas.height);
}, 1000 / 15);

addEvent(video, 'ended', function () {
  togglePlay.value = "play";
});

addEvent(video, 'canplay', function () {
  video.muted = true;
  document.querySelector('#duration').innerHTML = asTime(this.duration);
  startCanvas();
});


function startCanvas() {
  canvas.setAttribute('height', Math.floor(video.height));
  canvas.setAttribute('width', Math.floor(video.width));
  
  ctx.translate(canvas.width/2, canvas.height/2);
  ctx.scale(-1, 1);
  ctx.translate(-canvas.width/2, -canvas.height/2);
  ctx.drawImage(video, 0, 0, video.width, video.height, 0, 0, canvas.width, canvas.height);

  // var mirror = canvas.height * 0.6;
  // var grad = ctx.createLinearGradient(0, 0, 0, mirror);
  // grad.addColorStop(0, 'rgba(0, 0, 0, 0.5)');
  // grad.addColorStop(1, 'rgba(0, 0, 0, 1)');
  // ctx.fillStyle = grad;
  // ctx.rect(0, 0, canvas.width, mirror);
  // ctx.fill();
  // ctx.save();  
}

function asTime(t) {
  t = Math.round(t);
  var s = t % 60;
  var m = Math.round(t / 60);
  
  return two(m) + ':' + two(s);
}

function two(s) {
  s += "";
  if (s.length < 2) s = "0" + s;
  return s;
}
</script>
</body>
</html>