Image compression is an operation often used in our daily development. In today's situations where there are many demands, an uploaded image will be compressed into images of different proportions. It is also a very cumbersome thing to operate every time, so We have encapsulated an operation class for compressing images. I hope that after you encounter it, you will no longer have to worry about writing a lot of code to compress images.
Tools for compressing images:
<?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); } } ?>
Test:
<?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")); ?>
Result:
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