1. 使用Canvas绘制(1)矩形、(2)三角形、(3)扇形、(4)文本、(5)图像、(6)视频。

以下是使用Canvas绘制的示例代码：

1. 绘制矩形：

<canvas id="myCanvas" width="200" height="100"></canvas>
<script>
  var canvas = document.getElementById("myCanvas");
  var ctx = canvas.getContext("2d");
  ctx.fillStyle = "#FF0000";
  ctx.fillRect(0, 0, 150, 75);
</script>

2. 绘制三角形：

<canvas id="myCanvas" width="200" height="100"></canvas>
<script>
  var canvas = document.getElementById("myCanvas");
  var ctx = canvas.getContext("2d");
  ctx.beginPath();
  ctx.moveTo(100, 20);
  ctx.lineTo(20, 80);
  ctx.lineTo(180, 80);
  ctx.closePath();
  ctx.stroke();
</script>

3. 绘制扇形：

<canvas id="myCanvas" width="200" height="100"></canvas>
<script>
  var canvas = document.getElementById("myCanvas");
  var ctx = canvas.getContext("2d");
  ctx.beginPath();
  ctx.moveTo(100, 50);
  ctx.arc(100, 50, 40, 0, Math.PI/2, false);
  ctx.closePath();
  ctx.fillStyle = "#FF0000";
  ctx.fill();
</script>

4. 绘制文本：

<canvas id="myCanvas" width="200" height="100"></canvas>
<script>
  var canvas = document.getElementById("myCanvas");
  var ctx = canvas.getContext("2d");
  ctx.font = "30px Arial";
  ctx.fillText("Hello World", 10, 50);
</script>

5. 绘制图像：

<canvas id="myCanvas" width="200" height="100"></canvas>
<script>
  var canvas = document.getElementById("myCanvas");
  var ctx = canvas.getContext("2d");
  var img = new Image();
  img.src = "https://www.w3schools.com/tags/img_girl.jpg";
  img.onload = function() {
    ctx.drawImage(img, 0, 0);
  };
</script>

6. 播放视频：

<canvas id="myCanvas" width="640" height="360"></canvas>
<video id="myVideo" width="640" height="360" controls>
  <source src="https://www.w3schools.com/html/mov_bbb.mp4" type="video/mp4">
  Your browser does not support the video tag.
</video>
<script>
  var canvas = document.getElementById("myCanvas");
  var ctx = canvas.getContext("2d");
  var video = document.getElementById("myVideo");
  video.addEventListener('play', function() {
    var $this = this;
    (function loop() {
      if(!$this.paused && !$this.ended) {
        ctx.drawImage($this, 0, 0);
        setTimeout(loop, 1000 / 30);
      }
    })();
  }, 0);
</script>

以上是使用Canvas绘制矩形、三角形、扇形、文本、图像、视频的示例代码。