10 lines of code to generate a simple image, can not be generated! What to do with it

10 lines of code to generate a simple image, can not be generated!
Header ("Content-type:image/png");
$im = @imagecreate (100,100);
$background _color = imagecolorallocate ($im, 0,0,0);
$text _color =imagecolorallocate ($im, 255,255,255);

Imageline ($im, 1,1,350,25, $text _color);
Imagearc ($im, 200,15,20,20,35,190, $background _color);
Imagestring ($im, 5, 5, ten, "A simple Text String", $text _color);
Imagepng ($im);
Imagedestroy ($im);

------Solution--------------------
Did you install the GD library?
------Solution--------------------
Your code can be generated by: No problem
Confirm your php config file Extension=php_gd2.dll, this is already open ....

