七牛oss文档地址: https://developer.qiniu.com/kodo/sdk/1241/php
注册开通账户:https://portal.qiniu.com/signup
查看Access Key 和 Secret Key:https://portal.qiniu.com/user/key
github sdk: https://github.com/qiniu/php-sdk
图片处理文档:https://developer.qiniu.com/dora/api/1270/the-advanced-treatment-of-images-imagemogr2