php读取图片内容并输出到浏览器的实现代码

class imgdata{
        public $imgsrc;
        public $imgdata;
        public $imgform;
        public function getdir($source){
                $this->imgsrc  = $source;
        }
        public function img2data(){
                $this->_imgfrom($this->imgsrc);
                return $this->imgdata=fread(fopen($this->imgsrc,'rb'),filesize($this->imgsrc));       
        }
        public function data2img(){
                header("content-type:$this->imgform");
                echo $this->imgdata;
                //echo $this->imgform;
                //imagecreatefromstring($this->imgdata);
        }
        public function _imgfrom($imgsrc){
                $info=getimagesize($imgsrc);
                //var_dump($info);
                return $this->imgform = $info['mime'];
        }
}
$n = new imgdata;
$n -> getdir("1.jpg");
$n -> img2data();
$n -> data2img();