// img_manipulation():
// set the hidden fields and activate the form after that.

function img_manipulation(form_id){
	document.getElementById('tf_corner_left').value = tl_pos[0];
	document.getElementById('tf_corner_top').value = tl_pos[1];
	document.getElementById('br_corner_left').value = br_pos[0];
	document.getElementById('br_corner_top').value = br_pos[1];
	document.getElementById('img_scale').value = img_scale;
	
	document.getElementById(form_id).submit();
}