php实现图片居中裁剪并缩放

  1 <?php  2     /*  3     ** author 李攀  4     ** email 1061589921@qq.com  5     ** 实现移动开发中，多张图片排列.  6     */  7     $file = './234.png';  8     $Image = new image($file);  9     $width = $Image->getImageWidth(); 10     $height = $Image->getImageHeight(); 11     //判断该相片是否长宽相等 12     if($width != $height){ 13         //不相等则先以最小边为长度截取图片中心部分 14         if($width > $height){ 15             $x = ($width - $height) / 2; 16             $y = 0; 17             $width = $height; 18         }else{ 19             $y = ($height - $width) / 2; 20             $x = 0; 21             $height = $width; 22         } 23         $Image->crop($file,$width,$height,$x,$y,$file); 24     } 25  26     //等比例缩放图片 27     $dst_w = 100; 28     $dst_h = 100; 29     $Image->reduce($file,$dst_w,$dst_h,$file); 30 ?> 31 <?php 32 class image{ 33     private $_width; 34     private $_height; 35     private $_type; 36     //实例化时获取图片信息 37      function __construct($file_url){ 38          $info = getimagesize($file_url); 39          $this->_width = $info[0]; 40          $this->_height = $info[1]; 41          $type = $info['mime']; 42          $type = explode('/',$type); 43          $this->_type = $type[1]; 44      } 45      //返回图片类型 46      public function getImageType(){ 47          return $this->_type; 48      } 49      //返回图片宽度 50     public function getImageWidth(){ 51         return $this->_width; 52     } 53     //返回图片高度 54     public function getImageHeight(){ 55         return $this->_height; 56     } 57  58     /* 59     **图片裁剪 60     ** $tmp_image源文件 61     ** $dst_w 裁剪后的图片的宽度 62     ** $dst_h 裁剪后的图片的高度 63     ** $x 在源图的$x处坐标开始裁剪 64     ** $y 在源图的$y处坐标开始裁剪  65     */ 66     public function crop($tmp_image,$dst_w,$dst_h,$x,$y,$path){ 67         switch($this->_type){ 68             case 'jpeg': 69                 $src = imagecreatefromjpeg($tmp_image); 70                 break; 71             case 'gif': 72                 $src = imagecreatefromgif($tmp_image); 73                 break; 74             case 'png': 75                 $src = imagecreatefrompng($tmp_image); 76                 break; 77         } 78  79         $dst = imagecreatetruecolor($dst_w,$dst_h); 80         $color = imagecolorallocate($dst,255,255,255); 81         imagecolortransparent($dst,$color); 82         imagefill($dst,0,0,$color); 83         $bool = imagecopyresampled($dst,$src, 0,0,$x,$y, $dst_w,$dst_h,$dst_w,$dst_h); 84         switch($this->_type){ 85             case 'jpeg': 86                 imagejpeg($dst,$path,100); 87                 break; 88             case 'gif': 89                 imagegif($dst,$path); 90                 break; 91             case 'png': 92                 imagepng($dst,$path); 93                 break; 94         } 95  96         imagedestroy($src); 97         imagedestroy($dst); 98         return $bool; 99     }100 101     /*102     ** 等比例缩放图片103     ** $tmp_image源图104     ** $dst_w 缩放后的图片宽度105     ** $dst_h 缩放后的图片高度106     */107     public function reduce($tmp_image,$dst_w,$dst_h,$path){108         switch($this->_type){109             case 'jpeg':110                 $src = imagecreatefromjpeg($tmp_image);111                 break;112             case 'gif':113                 $src = imagecreatefromgif($tmp_image);114                 break;115             case 'png':116                 $src = imagecreatefrompng($tmp_image);117                 break;118         }119         $imagex = imagesx($src);120         $imagey = imagesy($src);121         $dst = imagecreatetruecolor($dst_w,$dst_h);122         $color = imagecolorallocate($dst,255,255,255);123         imagecolortransparent($dst,$color);124         imagefill($dst,0,0,$color);125         $bool = imagecopyresampled($dst,$src,0,0,0,0,$dst_w,$dst_h,$imagex,$imagey);126         switch($this->_type){127             case 'jpeg':128                 imagejpeg($dst,$path,100);129                 break;130             case 'gif':131                 imagegif($dst,$path);132                 break;133             case 'png':134                 imagepng($dst,$path);135                 break;136         }137         imagedestroy($src);138         imagedestroy($dst);139         return $bool;140     }141 }