ngx_http_image_filter_module

gistfile1.txt

location ~* /img/(.+)_(\d+)x(\d+)\.(jpg|gif|png)$ {            
    set $h $2;
    set $w $3;
    if ($h = "0") {
        rewrite /img/(.+)_(\d+)x(\d+)\.(jpg|gif|png)$ /img/$1.$4 last;
    }
    if ($w = "0") {
        rewrite /img/(.+)_(\d+)x(\d+)\.(jpg|gif|png)$ /img/$1.$4 last;
    }

    #根据给定的长宽生成缩略图
    image_filter resize $h $w;
    #原图最大2M，要裁剪的图片超过2M返回415错误，需要调节参数image_filter_buffer 
    image_filter_buffer 2M;                          

    #error_page  415              /img/notfound.jpg;
    try_files /img/$1.$4  /img/notfound.jpg;	
}

location ~* /img {

}