preloading a image

[ta2shop]

hy guys, i was searching for a javascript or somting to preload a image, an i found this, wich goes in the head of the page:

<SCRIPT language="JavaScript">
<!--
pic1= new Image(100,25); 
pic1.src="img/bg1.png"; 
//-->
</SCRIPT>

and this needs to go in the body part pf the page where the image is diplayed:

<SCRIPT language="JavaScript">
<!--
if (document.images)
{
  pic1= new Image(100,25); 
  pic1.src="http://someplace.com/image1.gif"; 
}
//-->
</SCRIPT>

but my image is in the css, in the body tag, so how can i change this so that it will work, or how sould i added to the css?
thanks.

[jacek]

Just doing

pic1= new Image(100,25);
pic1.src="img/bg1.png"; 

should start downloading the image, so you can use it where ever as you would normally do.

to change a background image with javascript

element.style.backgroundImage = 'file.png';

[ta2shop]

so just adding the head part of the code will solve my problem?
even for the bg imge that is caled with css?
thanks

[jacek]

so just adding the head part of the code will solve my problem?

Well it will start the image downloading.