php给上传图片加水印图案

<form action="<?=$_SERVER['PHP_SELF']?>" method="post" enctype="multipart/form-data" name="form1" id="form1">
<table width="486" border="0" align="center" cellpadding="0" cellspacing="0">
<tr>
<td width="498" height="28" background="image/top.gif"><div align="center" class="style2">上传图片</div></td>
</tr>
<tr>
<td> </td>
</tr>
<tr>
<td><div align="right">
<table width="426" border="0" align="center" cellpadding="0" cellspacing="0">
<tr>
<td width="50" height="32" nowrap="nowrap">路径：</td>
<td width="362"><input name="upfile" type="file" id="upfile" size="40" /></td>
</tr>

<tr>
<td height="27" colspan="2"><div align="center">
<input type="submit" name="Submit" value="提交" />
  
<input type="reset" name="Submit" value="重置" />
</div></td>
</tr>
</table>
</div>
<div align="center"></div></td>
</tr>
<tr>
<td> </td>
</tr><INPUT TYPE="hidden" name='action' value='doup'>
<tr>
<td height="28" background="image/top.gif"> </td>
</tr>
<tr>
<td> </td>
</tr>
</table>
</form>
<?
if($_POST['action']=='doup')
{
      $uptypes=array('image/jpg','image/jpeg','image/pjpeg','image/gif');//上传图片文件类型列表
      $wFile=$_FILES['upfile'];//取得文件路径
      $waterimg="water.gif";//水印图片路径 //print_r($wFile);
      if(in_array($wFile['type'], $uptypes))
      {//检查文件类型，若上传的文件为jpg或gif图片则加水印
       if(strstr($wFile['type'],"jp"))
       { //若上传图片类型为jpg,pjpeg,jpeg，则用imagecreatefromjpeg读取目标文件
                  $im = imageCreatefromjpeg($wFile['tmp_name']);
                  $wfilew=imagesx($im);//取得图片的宽
                  $wfileh=imagesy($im);//取得图片的高 }
            else
            {//否则若上传图片类型为gif，则用imagecreatefromgif读取目标文件
                  $im = imageCreatefromgif($wFile['tmp_name']);
                  $wfilew=imagesx($im);//取得图片的宽
                  $wfileh=imagesy($im);//取得图片的高
            }
       //设定混合模式
            imagealphablending($im, true);
            //读取水印文件
            $im2 = imagecreatefrompng($waterimg);//若水印图片为jpg，则此去可改为$im2 = imagecreatefromjpeg($waterimg) //$white = imagecolorallocate($im2, 255, 255, 255);
            // imagecolortransparent($im2,$white); //设透明色，这两句可不要 $waterw=imagesx($im2);//取得水印图片的宽
            $waterh=imagesy($im2);//取得水印图片的高
            //随机放水印到图片中
            $randval = rand(0,9);//在0-9之间产生随机数
            if($randval==0||$randval==3||$randval==2||$randval==8||$randval==7){//此处还可完善放更多位置
                  $wimgx=5;$wimgy=5;//放左上角
            }else{
                  $wimgx=$wfilew-5-$waterw;$wimgy=$wfileh-5-$waterh;//放右上角
            } //拷贝水印到目标文件
            imagecopy($im, $im2, $wimgx, $wimgy, 0, 0, $waterw,$waterh);
            
            //输出图片
            if(strstr($wFile['type'],"jp")){ //同上
                  imagejpeg($im,$wFile['tmp_name']);
            }else{
                  imagegif($im,$wFile['tmp_name']);
            }
            imagedestroy($im);
            imagedestroy($im2);
            copy($wFile['tmp_name'],$wFile['name']); //上传
      }else{
            echo "图片不符合！！";
      }
}
?>