import cv2 as cv
import matplotlib.pyplot as plt
import numpy as np

if __name__ == "__main__":
    img = cv.imread(r"img\iris.jpg", 0)
    fil1 = 1 / 16 * np.array([[1, 2, 1], [2, 4, 2], [1, 2, 1]])
    fil2 = 1 / 9 * np.array([[1, 1, 1], [1, 1, 1], [1, 1, 1]])
    fil3 = 1 / 10 * np.array([[1, 1, 1], [1, 2, 1], [1, 1, 1]])
    fil4 = np.array([[-1, -1, -1], [-1, 9, -1], [-1, -1, -1]])
    ImgSmoothed1 = cv.filter2D(img, -1, fil1, borderType=cv.BORDER_DEFAULT)
    ImgSmoothed2 = cv.filter2D(img, -1, fil2, borderType=cv.BORDER_DEFAULT)
    ImgSmoothed3 = cv.filter2D(img, -1, fil3, borderType=cv.BORDER_DEFAULT)
    ImgSharp = cv.filter2D(img, -1, fil4, borderType=cv.BORDER_DEFAULT)
    plt.figure()
    plt.subplot(221)
    plt.imshow(ImgSmoothed1, cmap="gray")
    plt.title("smoothed1")
    plt.subplot(222)
    plt.imshow(ImgSmoothed2, cmap="gray")
    plt.title("smoothed2")
    plt.subplot(223)
    plt.imshow(ImgSmoothed3, cmap="gray")
    plt.title("smoothed3")
    plt.subplot(224)
    plt.imshow(ImgSharp, cmap="gray")
    plt.title("sharp")
    plt.show()