php 图像和水印

生成图像

$img = imagecreate(400,400);
imagecolorallocate($img,255,255,255);
imageellipse($img,200,200,50,50,imagecolorallocate($img,255,0,0));
header('Content-type:image/png'); // mime type 对应表
imagepng($img);

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水印

$img = imagecreatefromjpeg('lydh.jpg');
imagestring($img,5,5,5,'mysterious',imagecolorallocate($img,255,255,0));
header('Content-type:image/png');
imagejpeg($img);