php为图片填加水印

<?php

/**

 * 加水印类，支持文字图片水印的透明度设置、水印图片背景透明。

 * 日期：2011-09-27

 * 作者：www.itwhy.org

 * 使用：

 *      $obj = new WaterMask($imgFileName);         //实例化对象

 *      $obj->$waterType = 1;                        //类型：0为文字水印、1为图片水印

 *      $obj->$transparent = 45;                 //水印透明度

 *      $obj->$waterStr = 'www.itwhy.org';           //水印文字

 *      $obj->$fontSize = 16;                        //文字字体大小

 *      $obj->$fontColor = array(255,0255);          //水印文字颜色（RGB）

 *      $obj->$fontFile = = 'AHGBold.ttf';           //字体文件

 *      $obj->output();                              //输出水印图片文件覆盖到输入的图片文件

 */

class WaterMask{

    public $waterType          = 1;               //水印类型：0为文字水印、1为图片水印

    public $pos                = 0;               //水印位置

    public $transparent        = 45;              //水印透明度

 

    public $waterStr           = 'www.itwhy.org';  //水印文字

    public $fontSize           = 16;              //文字字体大小

    public $fontColor          = array(255,0,255); //水印文字颜色（RGB）

    public $fontFile           = 'AHGBold.ttf';    //字体文件

 

    public $waterImg           = 'logo.png';       //水印图片

 

    private$srcImg             = '';               //需要添加水印的图片

    private$im                 = '';               //图片句柄

    private$water_im           = '';               //水印图片句柄

    private$srcImg_info        = '';               //图片信息

    private$waterImg_info      = '';               //水印图片信息

    private$str_w              = '';               //水印文字宽度

    private$str_h              = '';               //水印文字高度

    private$x                  = '';               //水印X坐标

    private$y                  = '';               //水印y坐标

 

    function__construct($img) {       //析构函数

        $this->srcImg =file_exists($img) ?$img : die('"'.$img.'" 源文件不存在！');

    }

    privatefunction imginfo() {               //获取需要添加水印的图片的信息，并载入图片。

        $this->srcImg_info =getimagesize($this->srcImg);

        switch($this->srcImg_info[2]) {

            case3:

                $this->im = imagecreatefrompng($this->srcImg);

                break1;

            case2:

                $this->im = imagecreatefromjpeg($this->srcImg);

                break1;

            case1:

                $this->im = imagecreatefromgif($this->srcImg);

                break1;

            default:

                die('原图片（'.$this->srcImg.'）格式不对，只支持PNG、JPEG、GIF。');

        }

    }

    privatefunction waterimginfo() {          //获取水印图片的信息，并载入图片。

        $this->waterImg_info =getimagesize($this->waterImg);

        switch($this->waterImg_info[2]) {

            case3:

                $this->water_im = imagecreatefrompng($this->waterImg);

                break1;

            case2:

                $this->water_im = imagecreatefromjpeg($this->waterImg);

                break1;

            case1:

                $this->water_im = imagecreatefromgif($this->waterImg);

                break1;

            default:

                die('水印图片（'.$this->srcImg.'）格式不对，只支持PNG、JPEG、GIF。');

        }

    }

    privatefunction waterpos() {              //水印位置算法

        switch($this->pos) {

            case0:     //随机位置

                $this->x = rand(0,$this->srcImg_info[0]-$this->waterImg_info[0]);

                $this->y = rand(0,$this->srcImg_info[1]-$this->waterImg_info[1]);

                break1;

            case1:     //上左

                $this->x = 0;

                $this->y = 0;

                break1;

            case2:     //上中

                $this->x = ($this->srcImg_info[0]-$this->waterImg_info[0])/2;

                $this->y = 0;

                break1;

            case3:     //上右

                $this->x =$this->srcImg_info[0]-$this->waterImg_info[0];

                $this->y = 0;

                break1;

            case4:     //中左

                $this->x = 0;

                $this->y = ($this->srcImg_info[1]-$this->waterImg_info[1])/2;

                break1;

            case5:     //中中

                $this->x = ($this->srcImg_info[0]-$this->waterImg_info[0])/2;

                $this->y = ($this->srcImg_info[1]-$this->waterImg_info[1])/2;

                break1;

            case6:     //中右

                $this->x =$this->srcImg_info[0]-$this->waterImg_info[0];

                $this->y = ($this->srcImg_info[1]-$this->waterImg_info[1])/2;

                break1;

            case7:     //下左

                $this->x = 0;

                $this->y =$this->srcImg_info[1]-$this->waterImg_info[1];

                break1;

            case8:     //下中

                $this->x = ($this->srcImg_info[0]-$this->waterImg_info[0])/2;

                $this->y =$this->srcImg_info[1]-$this->waterImg_info[1];

                break1;

            default:   //下右

                $this->x =$this->srcImg_info[0]-$this->waterImg_info[0];

                $this->y =$this->srcImg_info[1]-$this->waterImg_info[1];

                break1;

        }

    }

    privatefunction waterimg() {

        if($this->srcImg_info[0] <=$this->waterImg_info[0] ||$this->srcImg_info[1] <=$this->waterImg_info[1]){

            die('水印比原图大！');

        }

        $this->waterpos();

        $cut= imagecreatetruecolor($this->waterImg_info[0],$this->waterImg_info[1]);

        imagecopy($cut,$this->im,0,0,$this->x,$this->y,$this->waterImg_info[0],$this->waterImg_info[1]);

        $pct= $this->transparent;

        imagecopy($cut,$this->water_im,0,0,0,0,$this->waterImg_info[0],$this->waterImg_info[1]);

        imagecopymerge($this->im,$cut,$this->x,$this->y,0,0,$this->waterImg_info[0],$this->waterImg_info[1],$pct);

    }

    privatefunction waterstr() {

        $rect= imagettfbbox($this->fontSize,0,$this->fontFile,$this->waterStr);

        $w= abs($rect[2]-$rect[6]);

        $h= abs($rect[3]-$rect[7]);

        $fontHeight= $this->fontSize;

        $this->water_im = imagecreatetruecolor($w,$h);

        imagealphablending($this->water_im,false);

        imagesavealpha($this->water_im,true);

        $white_alpha= imagecolorallocatealpha($this->water_im,255,255,255,127);

        imagefill($this->water_im,0,0,$white_alpha);

        $color= imagecolorallocate($this->water_im,$this->fontColor[0],$this->fontColor[1],$this->fontColor[2]);

        imagettftext($this->water_im,$this->fontSize,0,0,$this->fontSize,$color,$this->fontFile,$this->waterStr);

        $this->waterImg_info =array(0=>$w,1=>$h);

        $this->waterimg();

    }

    functionoutput() {

        $this->imginfo();

        if($this->waterType == 0) {

            $this->waterstr();

        }else{

            $this->waterimginfo();

            $this->waterimg();

        }

        switch($this->srcImg_info[2]) {

            case3:

                imagepng($this->im,$this->srcImg);

                break1;

            case2:

                imagejpeg($this->im,$this->srcImg);

                break1;

            case1:

                imagegif($this->im,$this->srcImg);

                break1;

            default:

                die('添加水印失败！');

                break;

        }

        imagedestroy($this->im);

        imagedestroy($this->water_im);

    }

}

?>