图像调整实例

function resize_image($filename, $tmpname, $xmax, $ymax)

02

{

03	$ext = explode(".", $filename);

04	$ext = $ext[count($ext)-1];

05

06	if($ext == "jpg" || $ext == "jpeg")

07	$im = imagecreatefromjpeg($tmpname);

08	elseif($ext == "png")

09	$im = imagecreatefrompng($tmpname);

10	elseif($ext == "gif")

11	$im = imagecreatefromgif($tmpname);

12

13	$x = imagesx($im);

14	$y = imagesy($im);

15

16	if($x <= $xmax && $y <= $ymax)

17	return $im;

18

19	if($x >= $y) {

20	$newx = $xmax;

21	$newy = $newx * $y / $x;

22

}

23

else {

24	$newy = $ymax;

25	$newx = $x / $y * $newy;

26

}

27

28	$im2 = imagecreatetruecolor($newx, $newy);

29	imagecopyresized($im2, $im, 0, 0, 0, 0, floor($newx), floor($newy), $x, $y);

30	return $im2;

31

}