use the below.

[CODE=javascript]<SCRIPT language="Javas cript">
function funcName1() {

imgFile.src = "../image/imageName1.gif"

var getHeight = imgFile.height;
var getWidth = imgFile.width;

alert(getHeight );
alert(getWidth) ;
}
</SCRIPT>
[/CODE]
Thats it.

Regards
...