<?php     /**     * image zoom.     */     function imageZoom($filename, $w, $h) {         /* Arguments meaning */         /* $filename: the source of the name */         /* $w: you want get the image's width */         /* $h: you want get the imgage's height */         $arr = getimagesize($filename);         $src_w = $arr[0];         $src_h = $arr[1];         $src_t = $arr[2];         /*1 = GIF，2 = JPG，3 = PNG，4 = SWF，5 = PSD，6 = BMP，7 = TIFF(intel byte order)， = TIFF(motorola byte order)，9 = JPC，10 = JP2，11 = JPX，12 = JB2，13 = SWC， = IFF，15 = WBMP，16 = XBM*/         $src_m = $arr['mime'];         $src_img = imagecreatefromjpeg($filename);         if (($w / $src_w) >($h / $src_h)) {             $bili = $h / $src_h;         } else {             $bili = $w / $src_h;         }         $dst_w = $src_w * $bili;         $dst_h = $src_h * $bili;         $dst_img = imagecreatetruecolor($dst_w, $dst_h);         imagecopyresampled($dst_img, $src_img, 0, 0, 0, 0, $dst_w, $dst_h, $src_w, $src_h);         header("content-type:{$src_m}");         switch ($src_t) {             case 1:                 $imgout = "imagegif";                 break;             case 2:                 $imgout = "imagejpeg";                 break;             case 3:                 $imgout = "imagepng";                 break;             default:                 echo "The type was wrong!";                 break;         }         $dst_filename = "s_".$filename;         $imgout($dst_img, $dst_filename);         imagedestroy($dst_img);     }     $filename = 'gg.jpg';     imageZoom($filename, 100, 200);