diff --git a/CMakeLists.txt b/CMakeLists.txt
index d062edc..f23d0dc 100644
--- a/CMakeLists.txt
+++ b/CMakeLists.txt
@@ -3,7 +3,7 @@ cmake_minimum_required(VERSION 3.8.0 FATAL_ERROR)
 project(dsiflipencode)
 
 set(SOURCES
-	src/adpcm_encoder.cpp
+    src/adpcm_encoder.cpp
     src/lodepng.cpp
     src/main.cpp
     src/util.cpp
@@ -22,4 +22,10 @@ if(MSVC)
   target_compile_options(dsiflipencode PRIVATE /W4 /WX)
 else(MSVC)
   target_compile_options(dsiflipencode PRIVATE -Wall -Wextra -pedantic)
-endif(MSVC)
\ No newline at end of file
+endif(MSVC)
+
+if(NOT CMAKE_BUILD_TYPE)
+  set(CMAKE_BUILD_TYPE Release)
+endif()
+
+set(CMAKE_CXX_FLAGS_RELEASE "-O3")
\ No newline at end of file