怎样控制图片的透明度？

Question

<img border="0" onmouseout="low(this);" onmouseover="high(this);" src="INDEX.GIF" style="FILTER: alpha(opacity=10) border=0 curser:crosshair" width="50" height="50">
<SCRIPT language=JavaScript>
function high(which){
theobject=which
highlighting=setInterval("highlightit(theobject)",50)
}
function low(which){
clearInterval(highlighting)
which.filters.alpha.opacity=10
}
function highlightit(cur){
if (cur.filters.alpha.opacity<100)
cur.filters.alpha.opacity+=10
else if (window.highlighting)
clearInterval(highlighting)
}
</SCRIPT>

Answer 1

使用alpha滤镜style="filter:alpha(opacity=40)"如果不是把filter改成filters，不好意思记不清了，opacity是透明度100，是不透明，0是全透明

Answer 2

控制透明度<img id=testimg>
<script>
testimg.filters.alpha.opacity = 透明度的值
</script>

Answer 3

同意 runmin(稻草人)。实际上CSS2提供了很多滤镜的。 

Answer 4

请参考:
http://www.csdn.net/expert/topic/538/538456.xml