diff --git a/README.md b/README.md
index fb40f69c..bd441456 100755
--- a/README.md
+++ b/README.md
@@ -111,7 +111,7 @@ void TestCtrl::asyncHandleHttpRequest(const HttpRequestPtr& req,
 }
 ```
 
-**Don't be scared by the code, most of the above programs can be automatically generated by the command line tool `drogon_ctl` provided by drogon**. All the user needs to do is add their own business logic. In the example, the controller returns a `Hello, world!` string when the client accesses the `http://ip/test` URL.
+**Most of the above programs can be automatically generated by the command line tool `drogon_ctl` provided by drogon** (The cammand is `drogon_ctl create controller TestCtrl`). All the user needs to do is add their own business logic. In the example, the controller returns a `Hello, world!` string when the client accesses the `http://ip/test` URL.
 
 For JSON format response, we create the controller as follows:
 
diff --git a/drogon.jpg b/drogon.jpg
index b9bff69f..35cfca75 100644
Binary files a/drogon.jpg and b/drogon.jpg differ
diff --git a/examples/simple_example_test/main.cc b/examples/simple_example_test/main.cc
index 94e1886a..9f134fdd 100644
--- a/examples/simple_example_test/main.cc
+++ b/examples/simple_example_test/main.cc
@@ -26,6 +26,7 @@
 #define RED "\033[31m"   /* Red */
 #define GREEN "\033[32m" /* Green */
 
+#define JPG_LEN 44618
 using namespace drogon;
 
 void outputGood(const HttpRequestPtr &req, bool isHttps)
@@ -460,7 +461,7 @@ void doTest(const HttpClientPtr &client, std::promise<int> &pro, bool isHttps =
     client->sendRequest(req, [=, &pro](ReqResult result, const HttpResponsePtr &resp) {
         if (result == ReqResult::Ok)
         {
-            if (resp->getBody().length() == 52594)
+            if (resp->getBody().length() == JPG_LEN)
             {
                 outputGood(req, isHttps);
                 auto lastModified = resp->getHeader("last-modified");
@@ -566,7 +567,7 @@ void doTest(const HttpClientPtr &client, std::promise<int> &pro, bool isHttps =
     client->sendRequest(req, [=](ReqResult result, const HttpResponsePtr &resp) {
         if (result == ReqResult::Ok)
         {
-            if (resp->getBody().length() == 52594)
+            if (resp->getBody().length() == JPG_LEN)
             {
                 outputGood(req, isHttps);
             }