PHP mainly uses the GD library extension to operate image files. When we frequently use PHP to operate images, we will naturally encapsulate many functions, otherwise we will write too much repetitive code. When there are many functions related to pictures, we can consider organizing these functions, so we have the idea of ??encapsulating them into classes.

　There are four main steps to operating pictures:

1. Open pictures
2. Manipulate pictures
3. Output pictures
4. Destroy pictures

The three steps 1, 3, and 4 need to be written every time, and they are almost the same every time. The only step that really needs to be changed is the image manipulation step. Manipulating pictures is often done through one or more main GD functions.

This article encapsulates the four methods in the class, text watermark (imagettftext()), image watermark (imagecopymerge()), image compression, image cutting (imagecopyresampled()). The rest of the commonly used GD functions will not be described in detail. Go directly to the code:

<?<span>php 

</span><span>class</span><span> Image
{    
    </span><span>private</span><span> $info;

    </span><span>private</span><span> $image;
    </span><span>public</span><span> $type;
    </span><span>public</span><span> function __construct($src)
    {

        $</span><span>this</span>->info=<span>getimagesize($src);
        $</span><span>this</span>->type=image_type_to_extension($<span>this</span>->info[<span>'</span><span>2</span><span>'</span>],<span>false</span><span>);
        $fun</span>=<span>"</span><span>imagecreatefrom{$this->type}</span><span>"</span><span>;
        $</span><span>this</span>->image=<span>$fun($src);
    }
    </span><span>/*</span><span>*
     * 文字水印
     * @param  [type]  $font     字體
     * @param  [type]  $content  內(nèi)容
     * @param  [type]  $size     文字大小
     * @param  [type]  $col      文字顏色（四元數(shù)組）
     * @param  array   $location 位置 
     * @param  integer $angle    傾斜角度
     * @return [type]           
     </span><span>*/</span><span>public</span> function fontMark($font,$content,$size,$col,$location,$angle=<span>0</span><span>){
        $col</span>=imagecolorallocatealpha($<span>this</span>->image, $col[<span>'</span><span>0</span><span>'</span>], $col[<span>'</span><span>1</span><span>'</span>], $col[<span>'</span><span>2</span><span>'</span>],$col[<span>'</span><span>3</span><span>'</span><span>]);

        imagettftext($</span><span>this</span>->image, $size, $angle, $location[<span>'</span><span>0</span><span>'</span>], $location[<span>'</span><span>1</span><span>'</span><span>], $col,$font,$content);
    }
    
    </span><span>/*</span><span>*
     * 圖片水印
     * @param  [type] $imageMark 水印圖片地址
     * @param  [type] $dst       水印圖片在原圖片中的位置
     * @param  [type] $pct       透明度
     * @return [type]            
     </span><span>*/</span><span>public</span><span> function imageMark($imageMark,$dst,$pct){
        $info2</span>=<span>getimagesize($imageMark);
        $type</span>=image_type_to_extension($info2[<span>'</span><span>2</span><span>'</span>],<span>false</span><span>);
        $func2</span>=<span>"</span><span>imagecreatefrom</span><span>"</span><span>.$type;
        $water</span>=<span>$func2($imageMark);

        imagecopymerge($</span><span>this</span>->image, $water, $dst[<span>0</span>], $dst[<span>1</span>], <span>0</span>, <span>0</span>, $info2[<span>'</span><span>0</span><span>'</span>], $info2[<span>'</span><span>1</span><span>'</span><span>], $pct);
        imagedestroy($water);

    }
    </span><span>/*</span><span>*
     * 壓縮圖片
     * @param  [type] $thumbSize 壓縮圖片大小
     * @return [type]            [description]
     </span><span>*/</span><span>public</span><span> function thumb($thumbSize){
        $imageThumb</span>=imagecreatetruecolor($thumbSize[<span>0</span>], $thumbSize[<span>1</span><span>]);
        
        imagecopyresampled($imageThumb, $</span><span>this</span>->image, <span>0</span>, <span>0</span>, <span>0</span>, <span>0</span>, $thumbSize[<span>0</span>], $thumbSize[<span>1</span>], $<span>this</span>->info[<span>'</span><span>0</span><span>'</span>], $<span>this</span>->info[<span>'</span><span>1</span><span>'</span><span>]);
        imagedestroy($</span><span>this</span>-><span>image);
        $</span><span>this</span>->image=<span>$imageThumb;
    }
    </span><span>/*</span><span>*
    * 裁剪圖片
     * @param  [type] $cutSize  裁剪大小
     * @param  [type] $location 裁剪位置
     * @return [type]           [description]
     </span><span>*/</span><span>public</span><span> function cut($cutSize,$location){
         $imageCut</span>=imagecreatetruecolor($cutSize[<span>0</span>],$cutSize[<span>1</span><span>]);

         imagecopyresampled($imageCut, $</span><span>this</span>->image, <span>0</span>, <span>0</span>, $location[<span>0</span>], $location[<span>1</span>],$cutSize[<span>0</span>],$cutSize[<span>1</span>],$cutSize[<span>0</span>],$cutSize[<span>1</span><span>]);
         imagedestroy($</span><span>this</span>-><span>image);
         $</span><span>this</span>->image=<span>$imageCut;
     }
    </span><span>/*</span><span>*
     * 展現(xiàn)圖片
     * @return [type] [description]
     </span><span>*/</span><span>public</span><span> function show(){
        header(</span><span>"</span><span>content-type:</span><span>"</span>.$<span>this</span>->info[<span>'</span><span>mime</span><span>'</span><span>]);

        $funn</span>=<span>"</span><span>image</span><span>"</span>.$<span>this</span>-><span>type;

        $funn($</span><span>this</span>-><span>image);
    }
    </span><span>/*</span><span>*
     * 保存圖片
 * @param  [type] $newname 新圖片名
 * @return [type]          [description]
 </span><span>*/</span><span>public</span><span> function save($newname){
         header(</span><span>"</span><span>content-type:</span><span>"</span>.$<span>this</span>->info[<span>'</span><span>mime</span><span>'</span><span>]);

         $funn</span>=<span>"</span><span>image</span><span>"</span>.$<span>this</span>-><span>type;

         $funn($</span><span>this</span>->image,$newname.<span>'</span><span>.</span><span>'</span>.$<span>this</span>-><span>type);
     }
     </span><span>public</span><span> function __destruct(){
         imagedestroy($</span><span>this</span>-><span>image);
     }

 }

 </span>?>

If you need other operations, just add them to this class~~

The above introduces the encapsulation of adding, compressing, and cutting PHP image watermarks, including the content. I hope it will be helpful to friends who are interested in PHP tutorials.