//getimagesize()函数用于返回图像大小及相关信息，成功返回一个数组，失败则返回false并产生一条E_WARNING级的错误信息
list($width,$height,$type,$attr) = getimagesize("runoob-logo.png");
echo "宽度为".$width."<br>";
echo "高度为：".$height."<br>";
echo "类型为:".$type."."<br>";
echo "属性为:".$attr."<br>";
$remote_png_url = 'http://bluum.com/upload/image/002.jpg';
$image_data = getimagesize($remote_png_url);
print_r($image_data);