function img_popup(image_url, image_width, image_height, popup_rand) {
	screenwidth = false;
	screenwidth = screen.Width;
	if ( !screenwidth ) { screenwidth = window.outerWidth; }
	screenheight = false;
	screenheight = screen.Height;
	if ( !screenheight ) { screenheight = window.outerHeight; }
	if ( screenwidth < image_width || screenheight < image_height || image_width == null || image_height == null ) {
		window.open(image_url, 'limit_image_mod_popup_img_' + popup_rand, 'resizable=yes,top=0,left=0,screenX=0,screenY=0,scrollbars=yes', false);
	}else{
		window.open(image_url, 'limit_image_mod_popup_img_' + popup_rand, 'resizable=yes,top=0,left=0,screenX=0,screenY=0,height=' + image_height + ',width=' + image_width, false);
	}
}