diff --git a/README.md b/README.md
index c8a252a..afcfbb3 100644
--- a/README.md
+++ b/README.md
@@ -4,6 +4,7 @@
 
 * [1.图片上传](#1)
 * [2.图片拼接](#2)
+* [4.图片下载](#3)
 
 ------
 ## 前置安装
@@ -216,6 +217,26 @@ location /image_append {
 └── image_append.lua
 ```
 
+<h2 id="3">3.图片下载</h2>
 
+- music-room配置
 
+```nginx configuration
+# 子域名配置文件路径
+# /usr/local/openresty/nginx/conf.d/music-room.conf
 
+# server contex 中添加location
+
+#Donwload image use ngx.exec
+location /download_image2 {
+    content_by_lua_file /usr/local/openresty/nginx/conf/lua/download_image2.lua;
+}
+```
+
+- 添加lua脚本
+
+```bash
+/usr/local/openresty/resty_funcs
+.
+└── download_image.lua
+```
diff --git a/download_image/download_image.lua b/download_image/download_image.lua
new file mode 100644
index 0000000..96b395b
--- /dev/null
+++ b/download_image/download_image.lua
@@ -0,0 +1,7 @@
+-- Get download image id
+local download_image_id = string.match(ngx.var.request_uri, ".*/(.*)$")
+ngx.log(ngx.INFO , "Download image id: " .. download_image_id)
+
+-- Set redirect uri
+local uri = "/internal_file_upload/" .. download_image_id .. ".jpg"
+return ngx.exec(uri)
\ No newline at end of file