https://github.com/EagleWu/nginx-lua-imagemagick

http://sihuo.com/cdn_assets/photo/201411/06/545ae4109ac1b891759542.jpg

http://sihuo.com/cdn_assets/photo/201411/06/545ae4109ac1b891759542_320x320.jpg

http://sihuo.com/cdn_assets/photo/201411/06/545ae4109ac1b891759542_640_640.jpg

set $image_root "/opt/wwwroot/";图片输出目录

set $convert_bin "/opt/app/ImageMagick/bin/convert"; 是imagek安装路径

输出到 image_root 目录里面去 和原始文件在一起