先来看看啥叫基于URL动态生成缩略图。
/resize/<strong>400x200</strong>/images/thumb/e8ad3e43e64462c80e7f43fc51f7f948.jpg>400x200/images/thumb/e8ad3e43e64462c80e7f43fc51f7f948.jpg
我们改变上述链接中的400x200得到一个400x200的图片，改变为100x100得到一个100x100大小的图片，这个就是基于URL动态生成缩略图，后台只要保存一张原图即可。Copy

composer require intervention/image
composer require intervention/imagecacheCopy

<?php
return array(
    'route' => 'resize',
    'paths' => array(
        public_path('upload'),
        public_path('images')
    ),
    'templates' => array(
        '400x200' => 'App\Filters\MyFilter'
    ),
    'lifetime' => 43200,

);Copy

'route' => 'resize'Copy

'paths' => array( 'storage/uploads/images', public_path('img') )Copy

'templates' => array('400x200' => 'App\Filters\MyFilter'),Copy

<?php
namespace App\Filters;
use Intervention\Image\Image;
use Intervention\Image\Filters\FilterInterface;
class MyFilter implements FilterInterface {
      public function applyFilter(Image $image) {
             return $image->fit(400,  200);
      }
}Copy

'lifetime' => 43200Copy