自定义MVC框架之工具类-图像处理类

截止目前已经改造了4个类:

ubuntu:通过封装验证码类库一步步安装php的gd扩展

自定义MVC框架之工具类-分页类的封装

自定义MVC框架之工具类-文件上传类

图像处理类：

1，图片加水印处理( 支持任意位置与九宫格位置 )

2，图片缩放处理( 等比缩放，不变形裁剪 )

 <?php

 class Image{
     //文件路径
     protected $path;
     //是否允许随机文件名称
     protected $enableRandName;
     //文件类型
     protected $type;
     //错误号
     protected $errorNo;
     //错误信息
     protected $errorInfo;

     public function __construct( $_path = './', $_enableRandName = true ){
         $this->path = $_path;
         $this->enableRandName = $_enableRandName;
     }

     public function __get( $key ) {
         if( $key == 'errorNo' ) {
             return $this->errorNo;
         }else if( $key == 'errorInfo' ) {
             return $this->getErrorInfo();
         }
     }
     protected function getErrorInfo(){
         $info = '';
         switch( $this->errorNo ){
             case 1000:
                 $info = "水印或者图片源文件不存在";
                 break;
             case 1001:
                 $info = '水印图片的尺寸(宽或者高)大于图片本身';
                 break;
         }
         return $info;
     }

     //获取图片信息
     public static function getImageInfo( $imgPath ){
         $data = getimagesize( $imgPath );
         $info['width'] = $data[0];
         $info['height'] = $data[1];
         $info['mime'] = $data['mime'];
         return $info;
     }

     /*
      *    @srcImg 原图片
      *    @waterImg 水印图片
      *    @pos 水印位置
      *    @alpha 透明度
      *    @prefix 水印处理之后的图片前缀
      * */
     public function waterMark( $srcImg, $waterImg, $pos, $alpha, $prefix = 'ghostwu_' ){
         //检查图片和水印是否存在
         if( !file_exists( $srcImg )
             || !file_exists( $waterImg ) ) {
             $this->errorNo = 1000;
             return false;
         } 

         //获取图片和水印信息
         $srcImageInfo = self::getImageInfo( $srcImg );
         $waterImageInfo = self::getImageInfo( $waterImg );

         $this->type = explode( '/', $srcImageInfo['mime'] )[1];

         //检查水印和图片的尺寸, 水印是否能加在图片上
         if( !$this->check( $srcImageInfo, $waterImageInfo ) ) {
             $this->errorNo = 1001;
             return false;
         }

         //打开图片文件和水印文件资源
         $imgRes = self::openImage( $srcImg );
         $waterRes = self::openImage( $waterImg );

         //计算水印图片位置
         $waterPos = $this->calcPosition( $pos, $srcImageInfo, $waterImageInfo );

         //合成水印图片
         imagecopymerge ( $imgRes, $waterRes, $waterPos['x'], $waterPos['y'], 0, 0, $waterImageInfo['width'], $waterImageInfo['height'], $alpha );

         //得到文件的保存名字
         $saveName = $this->getFileName( $srcImg, $prefix );

         //拼凑完整的文件名称
         $fullPath = rtrim( $this->path, '/' ) . '/' . $saveName;

         //保存添加水印后的文件
         $this->saveImage( $imgRes, $fullPath );

         imagedestroy( $imgRes );
         imagedestroy( $waterRes );

         return $fullPath;
     }

     protected function saveImage( $imgRes, $fullPath ){
         $func = 'image' . $this->type;
         $func( $imgRes, $fullPath );
     }

     protected function getFileName( $imgPath, $prefix ){
         if ( $this->enableRandName ) {
             $saveName = $prefix . uniqid() . '.' . $this->type;
         }else {
             $saveName = $prefix . pathinfo( $imgPath )['filename'] . '.' . $this->type;
         }
         return $saveName;
     }

     protected function calcPosition( $pos, $imageInfo, $waterImageInfo ){
         $x = 0; $y = 0;
         switch( $pos ) {
             case 1: //左上角
                 $x = 0; $y = 0;
                 break;
             case 2: //上中
                 $x = ( $imageInfo['width'] - $waterImageInfo['width'] ) / 2;
                 $y = 0;
                 break;
             case 3: //右上角
                 $x = $imageInfo['width'] - $waterImageInfo['width'];
                 $y = 0;
                 break;
             case 4: //左边中间
                 $x = 0;
                 $y = ( $imageInfo['height'] - $waterImageInfo['height'] ) / 2;
                 break;
             case 5: //正中间
                 $x = ( $imageInfo['width'] - $waterImageInfo['width'] ) / 2;
                 $y = ( $imageInfo['height'] - $waterImageInfo['height'] ) / 2;
                 break;
             case 6: //右边中间
                 $x = $imageInfo['width'] - $waterImageInfo['width'];
                 $y = ( $imageInfo['height'] - $waterImageInfo['height'] ) / 2;
                 break;
             case 7: //左下角
                 $x = 0;
                 $y = $imageInfo['height'] - $waterImageInfo['height'];
                 break;
             case 8: //中间下面
                 $x = ( $imageInfo['width'] - $waterImageInfo['width'] ) / 2;
                 $y = $imageInfo['height'] - $waterInfo['height'];
                 break;
             case 9: //右下角
                 $x = $imageInfo['width'] - $waterImageInfo['width'];
                 $y = $imageInfo['height'] - $waterImageInfo['height'];
                 break;
             case 0: //随机位置
                 $x = mt_rand( 0, $imageInfo['width'] - $waterImageInfo['width'] );
                 $y = mt_rand( 0, $imageInfo['height'] - $waterImageInfo['height'] );
                 break;
         }
         return [ 'x' => $x, 'y' => $y ];
     }

     public static function openImage( $imagePath ){
         $mime = self::getImageInfo( $imagePath )['mime'];
         switch( $mime ){
             case 'image/gif':
                 $im = imagecreatefromgif( $imagePath );
                 break;
             case 'image/jpeg':
                 $im = imagecreatefromjpeg( $imagePath );
                 break;
             case 'image/png':
                 $im = imagecreatefrompng( $imagePath );
                 break;
             case 'image/wbmp':
                 $im = imagecreatefromwbmp( $imagePath );
                 break;
         }
         return $im;
     }

     public function check( $imgInfo, $waterInfo ){
         if( $imgInfo['width'] < $waterInfo['width']
            || $imgInfo['height'] < $waterInfo['height'] ){
             return false;
         }
         return true;
     }

     /*
      * @srcImg 原图片路径
      * @dstImg 目标图片路径
      * @newWidth 缩放后新的图片宽度
      * @newHeight 缩放后新的图片高度
      * */
     public function thumb( $srcImg, $newWidth, $newHeight, $prefix="thumb_" ){
         $srcIm = self::openImage( $srcImg );
         $srcInfo = self::getImageInfo( $srcImg );
         $srcW = $srcInfo['width'];
         $srcH = $srcInfo['height'];
         $this->type = explode( '/', $srcInfo['mime'] )[1];
         $ratio_w = $newWidth / $srcW;
         $ratio_h = $newHeight / $srcH;
         $ratio = 1.0;

         //缩放后的图片 宽度/高度 都比原图大或者小
         if( ( $ratio_w < 1 && $ratio_h < 1 ) || ( $ratio_w > 1 && $ratio_h > 1 ) ) {
             if( $ratio_w < $ratio_h ) {
                 $ratio = $ratio_h;
             }else {
                 $ratio = $ratio_w;
             }
             $tmp_w = (int)( $newWidth / $ratio );
             $tmp_h = (int)( $newHeight / $ratio );
             $tmp_im = imagecreatetruecolor( $tmp_w, $tmp_h );
             //生成一个以原图片最大边长,比例为ratio的中间图像
             imagecopy( $tmp_im, $srcIm, 0, 0, 0, 0, $tmp_w, $tmp_h );
             //定义一个目标尺寸的图像
             $newIm = imagecreatetruecolor( $newWidth, $newHeight );
             imagecopyresampled( $newIm, $tmp_im, 0, 0, 0, 0, $newWidth, $newHeight, $tmp_w, $tmp_h );
         }else {
         //缩放后的图片 宽度/高度 一个比原图大, 另一个比原图小
             $ratio = $ratio_h > $ratio_w ? $ratio_h : $ratio_w; //取比例大的那个值

             $tmp_w=(int)($srcW * $ratio);
             $tmp_h=(int)($srcH * $ratio);
             $tmp_im = imagecreatetruecolor($tmp_w, $tmp_h);

             imagecopyresampled($tmp_im, $srcIm, 0, 0, 0, 0, $tmp_w, $tmp_h, $srcW, $srcH );

             $newIm = imagecreatetruecolor($newWidth, $newHeight);
             imagecopy($newIm, $tmp_im, 0, 0, 0, 0, $newWidth, $newHeight);
         }
         //处理后的文件的保存名字
         $saveName = $this->getFileName( $newIm, $prefix );

         //拼凑完整的文件名称
         $fullPath = rtrim( $this->path, '/' ) . '/' . $saveName;

         $this->saveImage( $newIm, $fullPath );

         imagedestroy( $newIm );

         return $fullPath;
     }
 }

 $img = new Image();
 //$img->waterMark( '1.jpg', 'logo.png', 5, 30 );
 echo $img->thumb( '1.jpg', 330, 495 );

 ?>