js自动给图片添加图片的倒影

<SCRIPT LANGUAGE="JavaScript">
<!--
/**
 * reflection.js v1.5
 *
 * Contributors: Cow http://cow.neondragon.net
 *               Gfx http://www.jroller.com/page/gfx/
 *               Sitharus http://www.sitharus.com
 *               Andreas Linde http://www.andreaslinde.de
 *               Tralala, coder @ http://www.vbulletin.org
 *
 * Freely distributable under MIT-style license.
 */
 
/* From prototype.js */
document.getElementsByClassName = function(className) {
 var children = document.getElementsByTagName('*') || document.all;
 var elements = new Array();
 
 for (var i = 0; i < children.length; i++) {
  var child = children[i];
  var classNames = child.className.split(' ');
  for (var j = 0; j < classNames.length; j++) {
   if (classNames[j] == className) {
    elements.push(child);
    break;
   }
  }
 }
 return elements;
}
var Reflection = {
 defaultHeight : 0.5,
 defaultOpacity: 0.5,
 
 add: function(image, options) {
  Reflection.remove(image);
  
  doptions = { "height" : Reflection.defaultHeight, "opacity" : Reflection.defaultOpacity }
  if (options) {
   for (var i in doptions) {
    if (!options[i]) {
     options[i] = doptions[i];
    }
   }
  } else {
   options = doptions;
  }
 
  try {
   var d = document.createElement('div');
   var p = image;
   
   var classes = p.className.split(' ');
   var newClasses = '';
   for (j=0;j<classes.length;j++) {
    if (classes[j] != "reflect") {
     if (newClasses) {
      newClasses += ' '
     }
     
     newClasses += classes[j];
    }
   }
   var reflectionHeight = Math.floor(p.height*options['height']);
   var divHeight = Math.floor(p.height*(1+options['height']));
   
   var reflectionWidth = p.width;
 
   /* Copy original image's classes & styles to div */
   d.className = newClasses;
   p.className = 'reflected';
   
   d.style.cssText = p.style.cssText;
   p.style.cssText = ' ';
   
   if (document.all && !window.opera) {
    var reflection = document.createElement('img');
    reflection.src = p.src;
    reflection.style.width = reflectionWidth+'px';
    
    reflection.style.marginBottom = "-"+(p.height-reflectionHeight)+'px';
    reflection.style.filter = 'flipv progid:DXImageTransform.Microsoft.Alpha(opacity='+(options['opacity']*100)+', style=1, finishOpacity=0, startx=0, starty=0, finishx=0, finishy='+(options['height']*100)+')';
    
    d.style.width = reflectionWidth+'px';
    d.style.height = divHeight+'px';
    p.parentNode.replaceChild(d, p);
    
    d.appendChild(p);
    d.appendChild(reflection);
   } else {
    var canvas = document.createElement('canvas');
    var context = canvas.getContext("2d");
   
    canvas.style.height = reflectionHeight+'px';
    canvas.style.width = reflectionWidth+'px';
    canvas.height = reflectionHeight;
    canvas.width = reflectionWidth;
    
    d.style.width = reflectionWidth+'px';
    d.style.height = divHeight+'px';
    p.parentNode.replaceChild(d, p);
    
    d.appendChild(p);
    d.appendChild(canvas);
    
    context.save();
    
    context.translate(0,image.height-1);
    context.scale(1,-1);
    
    context.drawImage(image, 0, 0, reflectionWidth, image.height);
    context.restore();
    
    context.globalCompositeOperation = "destination-out";
    var gradient = context.createLinearGradient(0, 0, 0, reflectionHeight);
    
    gradient.addColorStop(1, "rgba(255, 255, 255, 1.0)");
    gradient.addColorStop(0, "rgba(255, 255, 255, "+(1-options['opacity'])+")");
 
    context.fillStyle = gradient;
    if (navigator.appVersion.indexOf('WebKit') != -1) {
     context.fill();
    } else {
     context.fillRect(0, 0, reflectionWidth, reflectionHeight*2);
    }
   }
  } catch (e) {
     }
 },
 
 remove : function(image) {
  if (image.className == "reflected") {
   image.className = image.parentNode.className;
   image.parentNode.parentNode.replaceChild(image, image.parentNode);
  }
 }
}
function addReflections() {
 var rimages = document.getElementsByClassName('reflect');
 for (i=0;i<rimages.length;i++) {
  var rheight = null;
  var ropacity = null;
  
  var classes = rimages[i].className.split(' ');
  for (j=0;j<classes.length;j++) {
   if (classes[j].indexOf("rheight") == 0) {
    var rheight = classes[j].substring(7)/100;
   } else if (classes[j].indexOf("ropacity") == 0) {
    var ropacity = classes[j].substring(8)/100;
   }
  }
  
  Reflection.add(rimages[i], { height: rheight, opacity : ropacity});
 }
}
var previousOnload = window.onload;
window.onload = function () { if(previousOnload) previousOnload(); addReflections(); }
//-->
</SCRIPT>
</head>
<body>
<img class="reflect" src="http://www.lixiaoliang.com/link/lixiaoliang.com88x31.jpg"/>
</body>