PHP处理图片的类

来源：互联网发布：excel做数据分布图编辑：程序博客网时间：2024/04/28 22:47

<?php

/**

* author:yagas

* email:yagas60@21cn.com

class Image
{
   /** 类保护变量 */
   protected $th_width    = 100;
   protected $th_height   = 50;
   protected $quality     = 85;   //图片质量
   protected $transparent = 50;   //水印透明度
   protected $background = "255,255,255"; //背景颜色


   /**
   * 生成缩略图文件
   * @param $src 原图文件
   * @param $dst 目标文件
   */
   public function thumb($src, $dst=null, $output=true)
   {
       $thumb = array($this->th_width, $this->th_height);
       $this->scale($src, $thumb, $dst, $output);
   }


   /**
   * 对图片按百分比进行缩放处理
   * @param string       $src     原图文件
   * @param string       $dst     输入的目标文件
   * @param float/array $zoom    缩放比例，浮点类型时按百分比绽放，数组类型时按指定大小时行缩放
   * @param boolean      $output 是否生成文件输出
   */
   public function scale($src, $dst=null, $zoom=1, $output=true)
   {
       if(!file_exists($src)) die('File not exists.');
       if(!$zoom) die('the zoom undefine.');

       $src_im     = $this->IM($src);
       $old_width = imagesx($src_im);

       if(is_float($zoom)) {
           //按百分比进行缩放
           $new_width = $old_width * $zoom;
       }
       elseif(is_array($zoom)) {
           //明确的缩放尺寸
           $new_width = $zoom[0];
       }

       //是否定义的缩放的高度
       if(!isset($zoom[1])) {
           //等比例缩放
           $resize_im = $this->imageresize($src_im, $new_width);
       }
       else {
           //非等比例缩放
           $resize_im = $this->imageresize($src_im, $new_width, $zoom[1]);
       }

       if(!$output) {
           header("Content-type: image/jpeg");
           imagejpeg($resize_im, null, $this->quality);
       }
       else {
           $new_file = empty($dst)? $src:$dst;
           imagejpeg($resize_im, $new_file, $this->quality);
       }

       imagedestroy($im);
       imagedestroy($nIm);
   }



   /**
   * 对图片进行裁切
   * @param $src    原始文件
   * @param $dst    目标文件
   * @param $output 是否生成目标文件
   */
   public function capture($src, $dst=null, $output=true) {
       if(!file_exists($src)) die('File not exists.');

       $width = $this->th_width;
       $height = $this->th_height;
       $src_im = $this->IM($src);
       $old_width = imagesx($src_im);
       $old_height = imagesy($src_im);

       $capture = imagecreatetruecolor($width, $height);
       $rgb = explode(",", $this->background);
       $white = imagecolorallocate($capture, $rgb[0], $rgb[1], $rgb[2]);
       imagefill($capture, 0, 0, $white);

       //当图片大于缩略图时进行缩放
       if($old_width > $width && $old_height>$height) {
           $resize_im = $this->imageresize($src_im, $width);

           //图片比例不合规范时，重新计算比例进行裁切
           if(imagesy($resize_im) < $height) {
               $proportion = $old_height/$this->th_height;
               $resize_im = $this->imageresize($src_im, $old_width/$proportion);
           }

           $posx = 0;
           $posy = 0;
       }
       else {
           //图片小于缩略图时将图片居中显示
           $posx      = ($width-$old_width)/2;
           $posy      = ($height-$old_height)/2;
           $resize_im = $src_im;
       }

       imagecopy($capture, $resize_im, $posx, $posy, 0, 0, imagesx($resize_im), imagesy($resize_im));

       if(!$output) {
           header("Content-type: image/jpeg");
           imagejpeg($capture, null, $this->quality);
       }
       else {
           $new_file = empty($dst)? $src:$dst;
           imagejpeg($capture, $new_file, $this->quality);
       }

       imagedestroy($src_im);
       @imagedestroy($resize_im);
       imagedestroy($capture);
   }

   /**
   * 写入水印图片
   * @param $src          需要写入水印的图片
   * @param $mark         水印图片
   * @param $transparent 水印透明度
   */
   public function mark($src, $mark, $dst='', $output=true)
   {
       $mark_info = getimagesize($mark);
       $src_info = getimagesize($src);
       list($mw,$mh) = $mark_info;
       list($sw,$sh) = $src_info;

       $px = $sw - $mw;
       $py = $sh - $mh;

       $im = $this->IM($src);
       $mim = $this->IM($mark);

       imagecopymerge($im, $mim, $px, $py, 0, 0, $mw, $mh, $this->transparent);

       if($output){
           $new_file = empty($dst)? $src:$dst;
           imagejpeg($im, $new_file, $this->quality);
       }
       else
       {
           header('Content-type: image/jpeg');
           imagejpeg($im);
       }
       imagedestroy($im);
       imagedestroy($mim);
   }



   /**
   * 通过文件，获取不同的GD对象
   */
   protected function IM($file)
   {
       if(!file_exists($file)) die('File not exists.');
       $info = getimagesize($file);
       switch($info['mime'])
       {
           case 'image/gif':
               $mim = imagecreatefromgif($file);
               break;

           case 'image/png':
               $mim = imagecreatefrompng($file);
               imagealphablending($mim, false);
               imagesavealpha($mim, true);
               break;

           case 'image/jpeg':
               $mim = imagecreatefromjpeg($file);
               break;

           default:
               die('File format errors.');
       }
       return $mim;
   }

   /**
   * 对图片进行缩放的处理
   * @param resource $src_im 图像GD对象
   * @param integer $width 图片的宽度
   * @param integer $height 图片的高度，如果不设置高度，将对图片进行等比例缩放
   * @return resuorce $im    返回一个GD对象
   */
   protected function imageresize($src_im, $width, $height=null) {
       $old_width = imagesx($src_im);
       $old_height = imagesy($src_im);
       $proportion = $old_width/$old_height;

       $new_width = $width;
       $new_height = is_null($height)? round($new_width / $proportion):$height;


       //创建新的图象并填充默认的背景色
       $im = imagecreatetruecolor($new_width, $new_height);
       $rgb = explode(",", $this->background);
       $white = imagecolorallocate($im, $rgb[0], $rgb[1], $rgb[2]);
       imagefill($im, 0, 0, $white);

       //对图片进行缩放
       imagecopyresized($im, $src_im, 0, 0, 0, 0, $new_width, $new_height, $old_width, $old_height);
       return $im;
   }

   /**
   * 类变量赋值
   */
   public function __set($key, $value)
   {
       $this->$key = $value;
   }


   /**
   * 获取类变量值
   */
   public function __get($key)
   {
       return $this->$key;
   }
}
?>