yum install -y epel-release
yum install -y https://mirrors.aliyun.com/epel/7/ppc64/Packages/s/salt-ssh-2015.5.10-2.el7.noarch.rpm https://mirrors.aliyun.com/epel/7/ppc64/Packages/s/salt-2015.5.10-2.el7.noarch.rpm python-msgpack python-zmq

然后在/etc/nginx/nginx.conf前面添加一行 load_module

user  nginx;
worker_processes  auto;

load_module "modules/ngx_http_image_filter_module.so";

更多版本可以进入 nginx 官方仓库

http://nginx.org/packages/centos/7/x86_64/RPMS/