​x
 
<!DOCTYPE html> 
<html> 
<body> 
​
<button onclick="getPlaySpeed()" type="button">默认的播放速度是多少？</button>
<button onclick="setPlaySpeed()" type="button">把视频设置为慢速播放</button>
<br />
<br />
<video id="video1" controls="controls">
  <source src="/example/html5/mov_bbb.mp4" type="video/mp4">
  <source src="/example/html5/mov_bbb.ogg" type="video/ogg">
  Your browser does not support HTML5 video.
</video>
​
<script>
myVid=document.getElementById("video1");
function getPlaySpeed()
  { 
  alert(myVid.defaultPlaybackRate);
  } 
function setPlaySpeed()
  { 
  myVid.defaultPlaybackRate=0.5;
  myVid.load();
  } 
</script> 
​
</body> 
</html>
​