You could try something like or similar to this:
<form enctype="multipart/form-data" method="post" action="upload.php" target="my_iframe">
Choose your file here:
<input name="uploaded_file" type="file"/>
<input type="submit" value="Upload It"/>
</form>
<!-- when the form is submitted, the server response will appear in this iframe -->
<script language="JavaScript">
<!--
function autoResize(id){
var newheight;
var newwidth;
if(document.getElementById){
newheight=document.getElementById(id).contentWindow.document .body.scrollHeight;
newwidth=document.getElementById(id).contentWindow.document .body.scrollWidth;
}
document.getElementById(id).height= (newheight) + "px";
document.getElementById(id).width= (newwidth) + "px";
}
//-->
</script>
<IFRAME name="my_iframe" SRC="upload.php" width="100%" height="200px" id="iframe1" marginheight="0" frameborder="0" onLoad="autoResize('iframe1');"></iframe>
Then put your php into "upload.php".