自己写的一个图片加水印类，暂时只支持水印图片，水印文字的还没有完善
代码不是很完善，欢迎大家交流指正！
调用方式：
先包含类文件
然后实例化类：
$img = new Images;
然后提供图片：
$img->imgpath(原图片路径及名称，水印图片路径及名称);
之后开始加水印：
$img->send();
说明：
send( strimg filename ) 这个方法有一个函数，可以省略，在省略的情况下，保存的图片路径和名称和原来的一样，如需保存成例外的图片，就在这里提供要保存的图片路径及名称
例外，还有一个方法，show(); 这个方法用于显示加好水印的图片
这个方法可以单独调用，但必须先调用 send()方法， 也可以连续调用： $img->send()->show();

   <?php  class Images{       private $imgA = '', $imgB = '';       private $imgWA = 0, $imgWB = 0, $typea = 0;       private $imgHA = 0, $imgHB = 0, $typeb = 0;       private $objecta, $objectb;       private $weizhi = 1; // 1坐上， 2中上， 3 右上， 4 中左， 5中部， 6 中右， 7， 下左， 8 下中， 9 下右       private $X = 0, $Y = 0;       private $okfile = '1.jpg';                       public function imgpath( $oldimg = '', $newing = '', $WeiZhi = 1 ) { //指定图片          $this->imgA   = $oldimg;          $this->imgB   = $newing;          $this->weizhi = $WeiZhi;         return $this;       }               public function send( $Name = '' ){           !empty( $Name ) or $Name = $this->imgA;           list($this->imgWA, $this->imgWB, $this->typea) = $this->imgread( $this->imgA );           list($this->imgHA, $this->imgHB, $this->typeb) = $this->imgread( $this->imgB );           $this->objecta = $this->openimg( $this->imgA, $this->typea );           $this->objectb = $this->openimg( $this->imgB, $this->typeb );           $this->WZ();           $this->start();           $this->over( $Name );           return $this;       }             private function WZ() {          switch( $this->weizhi ) {              case 2:                   $this->X = ( $this->imgWA - $this->imgHA ) / 2;                   break;              case 3:                   $this->X = ( $this->imgWA - $this->imgHA );                    break;              case 4:                   $this->Y = ( $this->imgWB - $this->imgHB ) / 2 ;                   break;              case 5:                   $this->X = ( $this->imgWA - $this->imgHA ) / 2;                   $this->Y = ( $this->imgWB - $this->imgHB ) / 2 ;                   break;              case 6:                   $this->X = ( $this->imgWA - $this->imgHA );                   $this->Y = ( $this->imgWB - $this->imgHB ) / 2 ;                   break;              case 7:                   $this->Y = ( $this->imgWB - $this->imgHB );                   break;              case 8:                   $this->X = ( $this->imgWA - $this->imgHA ) / 2;                   $this->Y = ( $this->imgWB - $this->imgHB );                   break;              case 9:                   $this->X = ( $this->imgWA - $this->imgHA );                   $this->Y = ( $this->imgWB - $this->imgHB );                   break;              default:                  $this->X = 0;                  $this->Y = 0;          }      }             private function openimg( $FileName = '', $type = 0 ) {          switch( $type ) {              case 1:                   $obj = imagecreatefromgif( $FileName ); break;              case 2:                   $obj = imagecreatefromjpeg( $FileName ); break;              case 3:                   $obj = imagecreatefrompng( $FileName ); break;              default:                  return false;          }         return $obj;      }             private function start(){          imagecopy( $this->objecta, $this->objectb, $this->X, $this->Y, 0, 0, $this->imgHA, $this->imgHB );      }             private function over( $name = '1.jpg' ) {          $this->okfile = $name;          switch ( $this->typea ) {              case 1:                  imagegif( $this->objecta, $name );break;              case 2:                  imagejpeg( $this->objecta, $name );break;              case 3:                  imagepng( $this->objecta, $name ); break;              default:                 return false;          }      }                           private function imgread( $FilePath = '' ) {          $Arr = getimagesize( $FilePath );          return array( $Arr[0], $Arr[1], $Arr[2] );      }                   public function show(){         @header('content-type:image/*');         echo @file_get_contents( $this->okfile );     }         }