new module: intensity_transform (includes gamma correction, log transfomration, autoscaling, contrast stretching)

build error fix: remove trailing whitespaces, casting types

minor edits based on alalek's feedback

removing trailing whitespace

using std::array for LUT argument

modules/intensity_transform/samples/intensity_transform.cpp

@@ -0,0 +1,39 @@
+#include "opencv2/core.hpp"
+#include "opencv2/imgcodecs.hpp"
+#include "opencv2/highgui.hpp"
+#include "opencv2/intensity_transform.hpp"
+
+#include <iostream>
+
+using namespace std;
+using namespace cv;
+using namespace cv::intensity_transform;
+
+int main(int argc, char **argv)
+{
+    if (argc != 2)
+    {
+        cerr << "Must input the path of the input image. Ex: intensity_transform image.jpg" << endl;
+        return -1;
+    }
+
+    // Read input image
+    Mat image = imread(argv[1]);
+
+    // Apply intensity transformations
+    Mat imgGamma, imgAutoscaled, imgLog, contrastStretch;
+    gammaCorrection(image, imgGamma, (float)(0.4));
+    autoscaling(image, imgAutoscaled);
+    logTransform(image, imgLog);
+    contrastStretching(image, contrastStretch, 70, 15, 120, 240);
+
+    // Display intensity transformation results
+    imshow("Original Image", image);
+    imshow("Autoscale", imgAutoscaled);
+    imshow("Gamma Correction", imgGamma);
+    imshow("Log Transformation", imgLog);
+    imshow("Contrast Stretching", contrastStretch);
+    waitKey(0);
+
+    return 0;
+}