PHP 按一定比例压缩图片，保持清晰度

图片压缩是我们日常开发中经常使用的操作，在如今需求很多的情况往往，上传的一张图片会被压缩成不同比例的图片，每次去操作也是一件非常繁琐的事情，于是进行了封装了一个压缩图片的操作类，希望大家遇到后，不用再为写很多压缩图片代码烦恼了。

压缩图片的工具类:

<?php
/**
 图片压缩操作类
 v1.0
*/
   class Image{
	   
	   private $src;
	   private $imageinfo;
	   private $image;
	   public  $percent = 0.1;
	   public function __construct($src){
		   
		   $this->src = $src;
		   
	   }
	   /**
	   打开图片
	   */
	   public function openImage(){
		   
		   list($width, $height, $type, $attr) = getimagesize($this->src);
		   $this->imageinfo = array(
				
				'width'=>$width,
				'height'=>$height,
				'type'=>image_type_to_extension($type,false),
				'attr'=>$attr
		   );
		   $fun = "imagecreatefrom".$this->imageinfo['type'];
		   $this->image = $fun($this->src);
	   }
	   /**
	   操作图片
	   */
	   public function thumpImage(){
		   
		    $new_width = $this->imageinfo['width'] * $this->percent;
			$new_height = $this->imageinfo['height'] * $this->percent;
			$image_thump = imagecreatetruecolor($new_width,$new_height);
			//将原图复制带图片载体上面，并且按照一定比例压缩,极大的保持了清晰度
			imagecopyresampled($image_thump,$this->image,0,0,0,0,$new_width,$new_height,$this->imageinfo['width'],$this->imageinfo['height']);
			imagedestroy($this->image);	
			$this->image = 	$image_thump;
	   }
	   /**
	   输出图片
	   */
	   public function showImage(){
		   
		    header('Content-Type: image/'.$this->imageinfo['type']);
			$funcs = "image".$this->imageinfo['type'];
			$funcs($this->image);
		   
	   }
	   /**
	   保存图片到硬盘
	   */
	   public function saveImage($name){
		   
		    $funcs = "image".$this->imageinfo['type'];
			$funcs($this->image,$name.'.'.$this->imageinfo['type']);
		   
	   }
	   /**
	   销毁图片
	   */
	   public function __destruct(){
		   
		   imagedestroy($this->image);
	   }
	   
   }
 

?>

<?php
		
		require 'image.class.php';
		$src = "001.jpg";
		$image = new Image($src);
		$image->percent = 0.2;
		$image->openImage();
		$image->thumpImage();
		$image->showImage();
		$image->saveImage(md5("aa123"));


?>