diff --git a/samples/directx/d3d10_interop.cpp b/samples/directx/d3d10_interop.cpp
index b2849cb1ce..d308797c01 100644
--- a/samples/directx/d3d10_interop.cpp
+++ b/samples/directx/d3d10_interop.cpp
@@ -1,3 +1,11 @@
+/*
+// Sample demonstrating interoperability of OpenCV UMat with Direct X surface
+// At first, the data obtained from video file or camera and
+// placed onto Direct X surface,
+// following mapping of this Direct X surface to OpenCV UMat and call cv::Blur
+// function. The result is mapped back to Direct X surface and rendered through
+// Direct X API.
+*/
 #define WIN32_LEAN_AND_MEAN
 #include <windows.h>
 #include <d3d10.h>
@@ -16,14 +24,6 @@
 using namespace std;
 using namespace cv;
 
-/*
-// Sample demonstrating interoperability of OpenCV UMat with Direct X surface
-// At first, the data obtained from video file or camera and
-// placed onto Direct X surface,
-// following mapping of this Direct X surface to OpenCV UMat and call cv::Blur
-// function. The result is mapped back to Direct X surface and rendered through
-// Direct X API.
-*/
 class D3D10WinApp : public D3DSample
 {
 public:
diff --git a/samples/directx/d3d11_interop.cpp b/samples/directx/d3d11_interop.cpp
index eb21c99814..5e8bc90905 100644
--- a/samples/directx/d3d11_interop.cpp
+++ b/samples/directx/d3d11_interop.cpp
@@ -1,3 +1,11 @@
+/*
+// Sample demonstrating interoperability of OpenCV UMat with Direct X surface
+// At first, the data obtained from video file or camera and
+// placed onto Direct X surface,
+// following mapping of this Direct X surface to OpenCV UMat and call cv::Blur
+// function. The result is mapped back to Direct X surface and rendered through
+// Direct X API.
+*/
 #define WIN32_LEAN_AND_MEAN
 #include <windows.h>
 #include <d3d11.h>
@@ -16,14 +24,6 @@
 using namespace std;
 using namespace cv;
 
-/*
-// Sample demonstrating interoperability of OpenCV UMat with Direct X surface
-// At first, the data obtained from video file or camera and
-// placed onto Direct X surface,
-// following mapping of this Direct X surface to OpenCV UMat and call cv::Blur
-// function. The result is mapped back to Direct X surface and rendered through
-// Direct X API.
-*/
 class D3D11WinApp : public D3DSample
 {
 public:
diff --git a/samples/directx/d3d9_interop.cpp b/samples/directx/d3d9_interop.cpp
index aca0245154..851bd7d520 100644
--- a/samples/directx/d3d9_interop.cpp
+++ b/samples/directx/d3d9_interop.cpp
@@ -1,3 +1,11 @@
+/*
+// Sample demonstrating interoperability of OpenCV UMat with Direct X surface
+// At first, the data obtained from video file or camera and
+// placed onto Direct X surface,
+// following mapping of this Direct X surface to OpenCV UMat and call cv::Blur
+// function. The result is mapped back to Direct X surface and rendered through
+// Direct X API.
+*/
 #define WIN32_LEAN_AND_MEAN
 #include <windows.h>
 #include <d3d9.h>
@@ -16,14 +24,6 @@
 using namespace std;
 using namespace cv;
 
-/*
-// Sample demonstrating interoperability of OpenCV UMat with Direct X surface
-// At first, the data obtained from video file or camera and
-// placed onto Direct X surface,
-// following mapping of this Direct X surface to OpenCV UMat and call cv::Blur
-// function. The result is mapped back to Direct X surface and rendered through
-// Direct X API.
-*/
 class D3D9WinApp : public D3DSample
 {
 public:
diff --git a/samples/directx/d3d9ex_interop.cpp b/samples/directx/d3d9ex_interop.cpp
index 7ca405b164..d59416bf0a 100644
--- a/samples/directx/d3d9ex_interop.cpp
+++ b/samples/directx/d3d9ex_interop.cpp
@@ -1,3 +1,11 @@
+/*
+// Sample demonstrating interoperability of OpenCV UMat with Direct X surface
+// At first, the data obtained from video file or camera and
+// placed onto Direct X surface,
+// following mapping of this Direct X surface to OpenCV UMat and call cv::Blur
+// function. The result is mapped back to Direct X surface and rendered through
+// Direct X API.
+*/
 #define WIN32_LEAN_AND_MEAN
 #include <windows.h>
 #include <d3d9.h>
@@ -16,14 +24,6 @@
 using namespace std;
 using namespace cv;
 
-/*
-// Sample demonstrating interoperability of OpenCV UMat with Direct X surface
-// At first, the data obtained from video file or camera and
-// placed onto Direct X surface,
-// following mapping of this Direct X surface to OpenCV UMat and call cv::Blur
-// function. The result is mapped back to Direct X surface and rendered through
-// Direct X API.
-*/
 class D3D9ExWinApp : public D3DSample
 {
 public:
diff --git a/samples/directx/d3dsample.hpp b/samples/directx/d3dsample.hpp
index e70a651055..8fc429a1e9 100644
--- a/samples/directx/d3dsample.hpp
+++ b/samples/directx/d3dsample.hpp
@@ -1,3 +1,7 @@
+/*
+// Sample demonstrating interoperability of OpenCV UMat with Direct X surface
+// Base class for Direct X application
+*/
 #include <string>
 #include <iostream>
 #include <queue>
diff --git a/samples/directx/winapp.hpp b/samples/directx/winapp.hpp
index 15e87788cf..bb9041f03a 100644
--- a/samples/directx/winapp.hpp
+++ b/samples/directx/winapp.hpp
@@ -1,3 +1,7 @@
+/*
+// Sample demonstrating interoperability of OpenCV UMat with Direct X surface
+// Base class for Windows application
+*/
 #define WIN32_LEAN_AND_MEAN
 #include <windows.h>
 #include <string>