location ~* ^/crop {
                root /home/wwwroot/$server_name/site_cache;
                set $width 240;
                set $height 180;
                set $dimens "";

       
                if ($uri ~* "^/crop_(\d+)x(\d+)/(.*)" ) {
                        set $width $1;
                        set $height $2;
                        set $image_path $3;
                        set $demins "_$1x$2";
                }

                if ($uri ~* "^/crop/(.*)" ) {
                        set $image_path $1;
                }




               国外服务器 set $image_uri image_crop/$image_path?width=$width&height=$height;

                if (!-f $request_filename) {
                        proxy_pass http://127.0.0.1/$image_uri;
                        break;
                }
                proxy_store /home/wwwroot/$server_name/site_cache/crop$demins/$image_path;
                proxy_store_access user:rw group:rw all:r;
                proxy_set_header Host $host;
                expires      30d;
                access_log off;
        }

        location /image_crop {
                alias /home/wwwroot/$server_name/;
                image_filter crop $arg_width $arg_height;
                image_filter_jpeg_quality 75;
                access_log off;
        }

比如访问 http://pics.v2ex.com/wp-content/uploads/465484/1.jpg 的缩略图

使用下面这样的链接可以访问到默认的裁剪为 240x180 的缩略图并缓存到硬盘上

http://pics.v2ex.com/crop/wp-content/uploads/465484/1.jpg

如何这样带后缀访问缩略图 http://pics.v2ex.com/wp-content/uploads/465484/1.jpg_crop

用的七牛的缩略图函数 ，七牛的免费流量超限了，想用自己闲置的 vps 搭建一个图床，弄好了，但是缩略图不会配置，在网上扒了一些资料，搞不定，求大牛该如何添加一个 if 语句

``` javascript

location ~* (.*\.(jpg|gif|png))/w/(.*)/h/(.*)$ {
root /home/wwwroot/$server_name/site_cache;
set $width $3;
set $height $4;
set $image_path $1;
set $demins "";
set $image_uri image_crop/$image_path?width=$width&height=$height;
if (!-f $request_filename) {
proxy_pass http://127.0.0.1/$image_uri;
break;
}
proxy_store /home/wwwroot/$server_name/site_cache/crop$demins/$image_path;
proxy_store_access user:rw group:rw all:r;
proxy_set_header Host $host;
expires 30d;
access_log off;


}
location /image_crop {
alias /home/wwwroot/$server_name/;
image_filter crop $arg_width $arg_height;
image_filter_jpeg_quality 75;
access_log off;
}
```
>搞定了，换了另外一种方法，访问形式是 xxx.jpg/w/240/h/180