diff --git a/CMakeLists.txt b/CMakeLists.txt
index f0ed799..abec9b8 100644
--- a/CMakeLists.txt
+++ b/CMakeLists.txt
@@ -46,6 +46,7 @@ set(TENMON_SRC
     main.cpp
     mainwindow.cpp mainwindow.h
     markedfiles.cpp markedfiles.h
+    mtfparam.h
     rawimage.cpp rawimage.h
     rawimage_sse.cpp
     scriptengine.cpp scriptengine.h
diff --git a/imagewidget.cpp b/imagewidget.cpp
index 0a5ab5a..6f2e6ea 100644
--- a/imagewidget.cpp
+++ b/imagewidget.cpp
@@ -359,7 +359,7 @@ void swPaint(std::shared_ptr<RawImage> &rawImage, float dx, float dy, float scal
     auto mtf = [&mtfParams](int i, float x)
     {
         x = (x - mtfParams.blackPoint[i]) / (mtfParams.whitePoint[i] - mtfParams.blackPoint[i]);
-        x = std::min(std::max(x, 0.0f), 1.0f);
+        x = std::clamp(x, 0.0f, 1.0f);
         return ((mtfParams.midPoint[i] - 1.0f) * x) / ((2.0f * mtfParams.midPoint[i] - 1.0f) * x - mtfParams.midPoint[i]);
     };
 
diff --git a/mtfparam.h b/mtfparam.h
new file mode 100644
index 0000000..64c31e7
--- /dev/null
+++ b/mtfparam.h
@@ -0,0 +1,11 @@
+#ifndef MTFPARAM_H
+#define MTFPARAM_H
+
+struct MTFParam
+{
+    float blackPoint[3] = {0.0f, 0.0f, 0.0f};
+    float midPoint[3] = {0.5f, 0.5f, 0.5f};
+    float whitePoint[3] = {1.0f, 1.0f, 1.0f};
+};
+
+#endif // MTFPARAM_H
diff --git a/stretchtoolbar.h b/stretchtoolbar.h
index 60693e0..d4306bd 100644
--- a/stretchtoolbar.h
+++ b/stretchtoolbar.h
@@ -4,16 +4,10 @@
 #include <QToolBar>
 #include <QStackedWidget>
 #include "stfslider.h"
+#include "mtfparam.h"
 
 class Image;
 
-struct MTFParam
-{
-    float blackPoint[3] = {0.0f, 0.0f, 0.0f};
-    float midPoint[3] = {0.5f, 0.5f, 0.5f};
-    float whitePoint[3] = {1.0f, 1.0f, 1.0f};
-};
-
 class StretchToolbar : public QToolBar
 {
     Q_OBJECT