Add docker badage

README.md

@@ -15,7 +15,8 @@
 [![](https://img.shields.io/twitch/status/winlinvip?style=social)](https://www.twitch.tv/winlinvip)
 [![](https://badgen.net/discord/members/yZ4BnPmHAd)](https://discord.gg/yZ4BnPmHAd)
 [![](https://opencollective.com/srs-server/tiers/badge.svg)](https://opencollective.com/srs-server/contribute)
-[![](https://img.shields.io/stackexchange/stackoverflow/r/17679565)](https://stackoverflow.com/questions/tagged/simple-realtime-server)
+[![](https://badgen.net/badge/srs/stackoverflow/orange?icon=terminal)](https://stackoverflow.com/questions/tagged/simple-realtime-server)
+[![](https://img.shields.io/docker/pulls/ossrs/srs)](https://hub.docker.com/r/ossrs/srs/tags)
 
 SRS/4.0，[Leo](https://github.com/ossrs/srs/wiki/Product#release40)，是一个简单高效的实时视频服务器，支持RTMP/WebRTC/HLS/HTTP-FLV/SRT。