diff --git a/include/hdrplus/merge.h b/include/hdrplus/merge.h
index 68956ea..d3aa550 100644
--- a/include/hdrplus/merge.h
+++ b/include/hdrplus/merge.h
@@ -2,6 +2,7 @@
 
 #include <vector>
 #include <opencv2/opencv.hpp> // all opencv header
+#include <cmath>
 #include "hdrplus/burst.h"
 
 namespace hdrplus
@@ -26,6 +27,35 @@ class merge
          */
         void process( const hdrplus::burst& burst_images, \
                       std::vector<std::vector<std::vector<std::pair<int, int>>>>& alignments);
+        
+    private:
+        cv::Mat cosineWindow1D(cv::Mat input, int window_size = 16) {
+            cv::Mat output = input.clone();
+            for (int i = 0; i < input.cols; ++i) {
+                output.at<float>(0, i) = 1. / 2. - 1. / 2. * cos(2 * M_PI * (input.at<float>(0, i) + 1 / 2.) / window_size);
+            }
+            return output;
+        }
+
+        cv::Mat cosineWindow2D(cv::Mat tile) {
+            int window_size = tile.rows; // Assuming square tile
+            cv::Mat output_tile = tile.clone();
+
+            cv::Mat window = cv::Mat::zeros(1, window_size, CV_32F);
+            for(int i = 0; i < window_size; ++i) {
+                window.at<float>(i) = i;
+            }
+
+            cv::Mat window_x = cosineWindow1D(window, window_size);
+            window_x = cv::repeat(window_x, window_size, 1);
+            cv::Mat window_2d = window_x.mul(window_x.t());
+
+            cv::Mat window_applied;
+            cv::multiply(tile, window_2d, window_applied, 1, CV_32F);
+            return window_applied;
+        }
+
+        std::vector<cv::Mat> getReferenceTiles(cv::Mat reference_image);
 };
 
 } // namespace hdrplus
diff --git a/src/merge.cpp b/src/merge.cpp
index 21b8204..ed7602b 100644
--- a/src/merge.cpp
+++ b/src/merge.cpp
@@ -14,24 +14,26 @@ void merge::process( const hdrplus::burst& burst_images, \
     std::tie(lambda_shot, lambda_read) = burst_images.bayer_images[burst_images.reference_image_idx].get_noise_params();
 
     // Obtain tiles
-    std::vector<cv::Mat> reference_tiles;
     cv::Mat reference_image = burst_images.grayscale_images_pad[0];
-    std::cout << reference_image.rows << " " << reference_image.cols << std::endl;
-    for (int y = 0; y < reference_image.rows - 8; y += 8) {
-        for (int x = 0; x < reference_image.cols - 8; x += 8) {
-            cv::Mat tile = reference_image(cv::Rect(x, y, 16, 16));
-            reference_tiles.push_back(tile);
-        }
-    }
-
-    
+    std::vector<cv::Mat> reference_tiles = getReferenceTiles(reference_image);
 
     // cv::Mat outputImg = reference_image.clone();
     // cv::cvtColor(outputImg, outputImg, cv::COLOR_GRAY2RGB);
     // cv::imwrite("ref.jpg", outputImg);
-    // cv::Mat outputImg1 = reference_tiles[0].clone();
+    // cv::Mat outputImg1 = cosineWindow2D(reference_tiles[0].clone());
     // cv::cvtColor(outputImg1, outputImg1, cv::COLOR_GRAY2RGB);
     // cv::imwrite("tile0.jpg", outputImg1);
 }
 
+std::vector<cv::Mat> merge::getReferenceTiles(cv::Mat reference_image) {
+    std::vector<cv::Mat> reference_tiles;
+    for (int y = 0; y < reference_image.rows - 8; y += 8) {
+        for (int x = 0; x < reference_image.cols - 8; x += 8) {
+            cv::Mat tile = reference_image(cv::Rect(x, y, 16, 16));
+            reference_tiles.push_back(tile);
+        }
+    }
+    return reference_tiles;
+}
+
 } // namespace hdrplus