PHP圖片加文字水印類庫

<?php

/*PHP圖片加文字水印類庫
該類庫暫時只支持文字水印，位置為右下角，顏色隨機
調用方法：
   1、在需要加水印的文件頂部引入類庫：
      include_once 'imageClass.php';
   2、聲明新類：
      $tpl=new image_fu;
   3、給圖片水印提供參數：
      $tpl->img(圖片路徑,水印文字,字體路徑,字體大小,字體角度);
      比如：$tpl->img('abc.jpg','這是水印文字','ziti.ttf',30,0)
*/
class image_fu{

 private $image;
 private $img_info;
 private $img_width;
 private $img_height;
 private $img_im;
 private $img_text;
 private $img_ttf='';
 private $img_new;
 private $img_text_size;
 private $img_jd;


 function img($img='',$txt='',$ttf='',$size=12,$jiaodu=0){
    if(isset($img)&&file_exists($img)){//檢測圖片是否存在
       $this->image   =$img; 
       $this->img_text=$txt;
       $this->img_text_size=$size;
       $this->img_jd=$jiaodu;
      if(file_exists($ttf)){
       $this->img_ttf=$ttf;
      }else{
       exit('字體文件：'.$ttf.'不存在！'); 
      }
       $this->imgyesno();
    }else{
      exit('圖片文件:'.$img.'不存在');
   } 
 }

 private function imgyesno(){

    $this->img_info  =getimagesize($this->image);
    $this->img_width =$this->img_info[0];//圖片寬
    $this->img_height=$this->img_info[1];//圖片高

    //檢測圖片類型
    switch($this->img_info[2]){
         case 1:$this->img_im = imagecreatefromgif($this->image);break; 
         case 2:$this->img_im = imagecreatefromjpeg($this->image);break; 
         case 3:$this->img_im = imagecreatefrompng($this->image);break; 
         default:exit('圖片格式不支持水印'); 
    }

       $this->img_text();
 }


 private function img_text(){

     imagealphablending($this->img_im,true);

     //設定顏色
      $color=imagecolorallocate($this->img_im,rand(0,255),rand(0,255),rand(0,255));
      $txt_height=$this->img_text_size;
      $txt_jiaodu=$this->img_jd;
      $ttf_im=imagettfbbox($txt_height,$txt_jiaodu,$this->img_ttf,$this->img_text);
      $w = $ttf_im[2] - $ttf_im[6]; 
      $h = $ttf_im[3] - $ttf_im[7]; 
      //$w = $ttf_im[7]; 
      //$h = $ttf_im[8]; 

      unset($ttf_im);

      $txt_y     =$this->img_height-$h;
      $txt_x     =$this->img_width-$w;
      //$txt_y     =0;
      //$txt_x     =0;



      $this->img_new=@imagettftext($this->img_im,$txt_height,$txt_jiaodu,$txt_x,$txt_y,$color,$this->img_ttf,$this->img_text);

     @unlink($this->image);//刪除圖片
    switch($this->img_info[2]) {//取得背景圖片的格式 
      case 1:imagegif($this->img_im,$this->image);break; 
      case 2:imagejpeg($this->img_im,$this->image);break; 
      case 3:imagepng($this->img_im,$this->image);break; 
      default: exit('水印圖片失敗'); 
    } 

 }


 //顯示圖片
 function img_show(){echo '<img src="'.$this->image.'" border="0" alt="'.$this->img_text."" />';}

 //釋放內存
 private function img_nothing(){
     unset($this->img_info); 
     imagedestroy($this->img_im); 
 }


}
?>
</pre>