add SharpenImage

.gitignore

@@ -8,3 +8,5 @@ SVMTest
 SVMTest.png
 
 DisplayImage
+
+SharpenImage

CMakeLists.txt

@@ -7,3 +7,6 @@ target_link_libraries( SVMTest ${OpenCV_LIBS} )
 
 add_executable( DisplayImage DisplayImage.cpp )
 target_link_libraries( DisplayImage ${OpenCV_LIBS} )
+
+add_executable( SharpenImage SharpenImage.cpp )
+target_link_libraries( SharpenImage ${OpenCV_LIBS} )

SharpenImage.cpp

@@ -0,0 +1,65 @@
+#include <stdio.h>
+#include <opencv2/opencv.hpp>
+
+using namespace cv;
+
+void
+Sharpen (const Mat & myImage, Mat & Result)
+{
+  CV_Assert (myImage.depth () == CV_8U);	// accept only uchar images
+
+  Result.create (myImage.size (), myImage.type ());
+  const int nChannels = myImage.channels ();
+
+  for (int j = 1; j < myImage.rows - 1; ++j)
+    {
+      const uchar *previous = myImage.ptr < uchar > (j - 1);
+      const uchar *current = myImage.ptr < uchar > (j);
+      const uchar *next = myImage.ptr < uchar > (j + 1);
+
+      uchar *output = Result.ptr < uchar > (j);
+
+      for (int i = nChannels; i < nChannels * (myImage.cols - 1); ++i)
+	{
+	  *output++ = saturate_cast < uchar > (5 * current[i]
+					       - current[i - nChannels] -
+					       current[i + nChannels] -
+					       previous[i] - next[i]);
+	}
+    }
+
+  Result.row (0).setTo (Scalar (0));
+  Result.row (Result.rows - 1).setTo (Scalar (0));
+  Result.col (0).setTo (Scalar (0));
+  Result.col (Result.cols - 1).setTo (Scalar (0));
+}
+
+int
+main (int argc, char **argv)
+{
+  if (argc != 2)
+    {
+      printf ("Usage: SharpenImage image.jpg\n");
+      return -1;
+    }
+
+  Mat image;
+  image = imread (argv[1], 1);
+
+  if (argc != 2 || !image.data)
+    {
+      printf ("No image data\n");
+      return -1;
+    }
+
+  Mat result;
+  Sharpen (image, result);
+
+  namedWindow ("Sharpen Image", CV_WINDOW_AUTOSIZE);
+  // imshow("Sharpen Image", image);
+  imshow ("Sharpen Image", result);
+
+  waitKey (0);
+
+  return 0;
+}