diff --git a/ccv/sheet3/CMakeLists.txt b/ccv/sheet3/CMakeLists.txt
new file mode 100644
index 0000000..9d9ebe8
--- /dev/null
+++ b/ccv/sheet3/CMakeLists.txt
@@ -0,0 +1,13 @@
+cmake_minimum_required(VERSION 3.5)
+project(sheet3)
+
+set(CMAKE_CXX_STANDARD 11)
+
+find_package( OpenCV REQUIRED )
+
+add_executable(sheet3 main.cpp)
+add_executable(sheet3-exercise1 exercise1.cpp)
+add_executable(sheet3-exercise3 exercise3.cpp)
+target_link_libraries(sheet3 ${OpenCV_LIBS})
+target_link_libraries(sheet3-exercise1 ${OpenCV_LIBS})
+target_link_libraries(sheet3-exercise3 ${OpenCV_LIBS})
diff --git a/ccv/sheet3/DSC09506.JPG b/ccv/sheet3/DSC09506.JPG
new file mode 100644
index 0000000..4dab65e
Binary files /dev/null and b/ccv/sheet3/DSC09506.JPG differ
diff --git a/ccv/sheet3/exercise1.cpp b/ccv/sheet3/exercise1.cpp
new file mode 100644
index 0000000..ef91093
--- /dev/null
+++ b/ccv/sheet3/exercise1.cpp
@@ -0,0 +1,44 @@
+#include <opencv2/opencv.hpp>
+
+int main(int argc, char** argv ) {
+// exercise 1
+
+// matrix M
+  float m[] = {1.0, 1.0, 1.0, 1.0, 2.0, 1.0, 1.0, 1.0, 1.0};
+  cv::Mat M(3, 3, CV_32FC1, m);
+// gaussian filter kernel
+  float g[] = {1, 2, 1, 2, 4, 2, 1, 2, 1};
+  cv::Mat G(3, 3, CV_32FC1, g);
+  G = G * 0.0625;
+// output G
+  std::cout << G << std::endl << std::endl;
+
+// convolve 1.
+  cv::Mat M_1;
+  cv::filter2D(M, M_1, -1, G, cv::Point(-1, -1), 0, cv::BORDER_CONSTANT);
+// output M_1
+  std::cout << M_1 << std::endl << std::endl;
+
+// convolve 2.
+  float g_1[] = {1, 2, 1};
+  cv::Mat G_1(1, 3, CV_32FC1, g_1);
+  G_1 = G_1 * 0.25;
+  float g_2[] = {1, 2, 1};
+  cv::Mat G_2(3, 1, CV_32FC1, g_2);
+  G_2 = G_2 * 0.25;
+// output G_1, G_2
+  std::cout << G_1 << std::endl << std::endl;
+  std::cout << G_2 << std::endl << std::endl;
+
+  cv::Mat M_2;
+  cv::Mat M_3;
+  cv::filter2D(M, M_2, -1, G_1, cv::Point(-1, -1), 0, cv::BORDER_CONSTANT);
+  cv::filter2D(M_2, M_3, -1, G_2, cv::Point(-1, -1), 0, cv::BORDER_CONSTANT);
+// output M_3
+  std::cout << M_3 << std::endl << std::endl;
+
+// convolve 3.
+  cv::Mat M_4;
+  cv::GaussianBlur(M, M_4, cv::Size(3, 3), 0, 0, cv::BORDER_CONSTANT);
+  std::cout << M_4 << std::endl << std::endl;
+}
diff --git a/ccv/sheet3/exercise3.cpp b/ccv/sheet3/exercise3.cpp
new file mode 100644
index 0000000..70bd9ca
--- /dev/null
+++ b/ccv/sheet3/exercise3.cpp
@@ -0,0 +1,55 @@
+#include <opencv2/opencv.hpp>
+
+int main(int argc, char** argv ) {
+  if ( argc != 2 )
+  {
+    printf("usage: <Image_Path>\n");
+    return -1;
+  }
+
+  cv::Mat image;
+  image = cv::imread(argv[1], cv::ImreadModes::IMREAD_COLOR);
+  cv::Mat image_gray;
+  cv::cvtColor(image, image_gray, cv::COLOR_BGR2GRAY);
+  cv::Mat image_float;
+  image_gray.convertTo(image_float, CV_32F);
+
+  cv::Mat G_1;
+  cv::Mat G_2;
+  cv::GaussianBlur(image_float, G_1, cv::Size(3, 3), 3, 3, cv::BORDER_CONSTANT);
+  cv::GaussianBlur(image_float, G_2, cv::Size(3, 3), 11, 11, cv::BORDER_CONSTANT);
+  cv::Mat image_filtered = G_1 - G_2;
+
+  cv::imshow("Filtered (3 - 11)", image_filtered);
+  cv::waitKey(0);
+
+  cv::GaussianBlur(image_float, G_1, cv::Size(3, 3), 3, 3, cv::BORDER_CONSTANT);
+  cv::GaussianBlur(image_float, G_2, cv::Size(3, 3), 7, 7, cv::BORDER_CONSTANT);
+  image_filtered = G_1 - G_2;
+
+  cv::imshow("Filtered (3 - 7)", image_filtered);
+  cv::waitKey(0);
+
+  cv::GaussianBlur(image_float, G_1, cv::Size(3, 3), 5, 5, cv::BORDER_CONSTANT);
+  cv::GaussianBlur(image_float, G_2, cv::Size(3, 3), 7, 7, cv::BORDER_CONSTANT);
+  image_filtered = G_1 - G_2;
+
+  cv::imshow("Filtered (5 - 7)", image_filtered);
+  cv::waitKey(0);
+
+  cv::GaussianBlur(image_float, G_1, cv::Size(3, 3), 11, 11, cv::BORDER_CONSTANT);
+  cv::GaussianBlur(image_float, G_2, cv::Size(3, 3), 3, 3, cv::BORDER_CONSTANT);
+  image_filtered = G_1 - G_2;
+  image_float.convertTo(image_gray, CV_8U);
+
+  cv::imshow("Filtered (11 - 3)", image_filtered);
+  cv::waitKey(0);
+
+  cv::GaussianBlur(image_float, G_1, cv::Size(3, 3), 9, 9, cv::BORDER_CONSTANT);
+  cv::GaussianBlur(image_float, G_2, cv::Size(3, 3), 5, 5, cv::BORDER_CONSTANT);
+  image_filtered = G_1 - G_2;
+
+  cv::imshow("Filtered (9 - 5)", image_filtered);
+  cv::waitKey(0);
+}
+
diff --git a/ccv/sheet3/main.cpp b/ccv/sheet3/main.cpp
new file mode 100644
index 0000000..7b53758
--- /dev/null
+++ b/ccv/sheet3/main.cpp
@@ -0,0 +1,24 @@
+#include <opencv2/opencv.hpp>
+
+int main(int argc, char** argv ) {
+  if ( argc != 2 )
+  {
+    printf("usage: main.out <Image_Path>\n");
+    return -1;
+  }
+
+  // exercise 2
+  cv::Mat image;
+  image = cv::imread(argv[1], cv::ImreadModes::IMREAD_COLOR);
+  int kmax = 50;
+  cv::Mat Matrix_convoluted;
+  for (int k = 3; k < kmax; k+=2) {
+    cv::GaussianBlur(image, Matrix_convoluted, cv::Size(k, k), 0, 0, cv::BORDER_CONSTANT);
+    std::string imageName = "Kernel (";
+    imageName = imageName + std::to_string(k) + ", " + std::to_string(k) + ")";
+    cv::imshow(imageName, Matrix_convoluted);
+    cv::waitKey(500);
+  }
+
+  return 0;
+}