python+opencv 图像梯度

import cv2 as cv
import numpy as np


def laplacian_demo(image):
    # dst = cv.Laplacian(image, cv.CV_32F)
    # lpls = cv.convertScaleAbs(dst)
    # 自己定义掩膜
    kernel = np.array([[1, 1, 1], [1, -8, 1], [1, 1, 1]])
    dst = cv.filter2D(image, cv.CV_32F, kernel=kernel)
    lpls = cv.convertScaleAbs(dst)
    cv.imshow('laplaciandemo', lpls)


def sobel_demo(image):
    grad_x = cv.Sobel(image, cv.CV_32F, 1, 0)
    grad_y = cv.Sobel(image, cv.CV_32F, 0, 1)
    # 全部转到8位的图像上，且都是正数
    gradx = cv.convertScaleAbs(grad_x)
    grady = cv.convertScaleAbs(grad_y)
    cv.imshow('gradient-x', gradx)
    cv.imshow('gradient-y', grady)

    gradxy = cv.addWeighted(gradx, 0.5, grady, 0.5, 0)
    cv.imshow('gradient', gradxy)


src = cv.imread('C:/Users/Y/Pictures/Saved Pictures/demo.png')
cv.namedWindow('input image', cv.WINDOW_AUTOSIZE)
cv.imshow('input image', src)
laplacian_demo(src)
cv.waitKey(0)
cv.destroyAllWindows()