diff --git a/README.md b/README.md
index 80c2ed7..e302bab 100644
--- a/README.md
+++ b/README.md
@@ -1,6 +1,13 @@
 blocky
 ====
 
+## CMake command
+
+When you built openh264 on `/home/user/openh264`:
+```
+cmake -DCMAKE_CXX_FLAGS=-isystem\ /home/user/openh264/codec/api\ -L/home/user/openh264 ..
+```
+
 ## ffmpeg useful commands
 
 ```
diff --git a/thirdparty/CMakeLists.txt b/thirdparty/CMakeLists.txt
index 2dd1a71..df2665a 100644
--- a/thirdparty/CMakeLists.txt
+++ b/thirdparty/CMakeLists.txt
@@ -120,6 +120,26 @@ target_sources(implot
 )
 
 
+# ---- minimp4 ----
+# repository: https://github.com/lieff/minimp4
+# license   : CC0
+
+FetchContent_Declare(
+  minimp4
+  URL "https://github.com/lieff/minimp4/archive/4575afb4f69ace25a1a048e25cc86bf8c8d14f2b.zip"
+)
+FetchContent_Populate(minimp4)
+
+add_library(minimp4)
+target_include_directories(minimp4 PUBLIC SYSTEM ${minimp4_SOURCE_DIR})
+target_sources(minimp4
+  PUBLIC
+    "${minimp4_SOURCE_DIR}/minimp4.h"
+  PRIVATE
+    minimp4.c
+)
+
+
 # ---- stb ----
 FetchContent_Declare(
   stb
diff --git a/thirdparty/minimp4.c b/thirdparty/minimp4.c
new file mode 100644
index 0000000..909b403
--- /dev/null
+++ b/thirdparty/minimp4.c
@@ -0,0 +1,2 @@
+#define MINIMP4_IMPLEMENTATION
+#include <minimp4.h>