diff --git a/include/ctrff/helper.hpp b/include/ctrff/helper.hpp
index 727bd56..01aa437 100644
--- a/include/ctrff/helper.hpp
+++ b/include/ctrff/helper.hpp
@@ -12,5 +12,6 @@ CTRFF_API void RGBA2RGB565(ctrff::u16 *out, const std::vector<ctrff::u8> &img,
                            const int &w, const int &h);
 CTRFF_API std::vector<ctrff::u8> DownscaleImage(
     const std::vector<ctrff::u8> &img, int w, int h, int scale);
+CTRFF_API void Flip(std::vector<u8> &buf, int w, int h);
 CTRFF_API ctrff::u32 TileIndex(const int &x, const int &y, const int &w);
 }  // namespace ctrff
\ No newline at end of file
diff --git a/include/ctrff/types.hpp b/include/ctrff/types.hpp
index a2131a8..35bb6b5 100644
--- a/include/ctrff/types.hpp
+++ b/include/ctrff/types.hpp
@@ -58,6 +58,7 @@ SOFTWARE.
 #include <fstream>
 #include <iostream>
 #include <memory>
+#include <numeric>
 #include <sstream>
 #include <stdexcept>
 #include <string>
diff --git a/source/helper.cpp b/source/helper.cpp
index 16dd905..fd7ea30 100644
--- a/source/helper.cpp
+++ b/source/helper.cpp
@@ -87,6 +87,20 @@ CTRFF_API std::vector<ctrff::u8> ctrff::DownscaleImage(
   return res;
 }
 
+CTRFF_API void ctrff::Flip(std::vector<ctrff::u8> &buf, int w, int h) {
+  std::vector<ctrff::u8> tmp = buf;
+  for (int x = 0; x < w; x++) {
+    for (int y = 0; y < h; y++) {
+      int src = (y * w + x) * 4;
+      int dst = ((h - 1 - y) * w + x) * 4;
+      buf[dst + 0] = tmp[src + 0];
+      buf[dst + 1] = tmp[src + 1];
+      buf[dst + 2] = tmp[src + 2];
+      buf[dst + 3] = tmp[src + 3];
+    }
+  }
+}
+
 CTRFF_API void ctrff::String2U16(ctrff::u16 *res, const std::string &src,
                                  size_t max) {
   /// GOT FORCED TO REPLACE std::wstring_convert by some