实现Sobel算子滤波、Robers算子滤波、Laplace算子滤波

前几天，老师布置了这样一个任务，读取图片并显示，反色后进行显示；进行Sobel算子滤波，然后反色，进行显示；进行Robers算子滤波，然后反色，进行显示。我最后加上了Laplace算子滤波，进行了比较。下面我来讲一下我的实现方法：

一、实现过程

思路：先完成每种函数的算法，接下来是反色函数，最后实现。

import cv2

import numpy as np

# robert 算子[[-1,-1],[1,1]]

def robert_suanzi(img):

r, c = img.shape

r_sunnzi = [[-1,-1],[1,1]]

for x in range(r):

for y in range(c):

if (y + 2 <= c) and (x + 2 <= r):

imgChild = img[x:x+2, y:y+2]

list_robert = r_sunnzi*imgChild

img[x, y] = abs(list_robert.sum()) # 求和加绝对值

return img

# # sobel算子的实现

def sobel_suanzi(img):

r, c = img.shape

new_image = np.zeros((r, c))

new_imageX = np.zeros(img.shape)

new_imageY = np.zeros(img.shape)

s_suanziX = np.array([[-1,0,1],[-2,0,2],[-1,0,1]]) # X方向

s_suanziY = np.array([[-1,-2,-1],[0,0,0],[1,2,1]])

for i in range(r-2):

for j in range(c-2):

new_imageX[i+1, j+1] = abs(np.sum(img[i:i+3, j:j+3] * s_suanziX))

new_imageY[i+1, j+1] = abs(np.sum(img[i:i+3, j:j+3] * s_suanziY))

new_image[i+1, j+1] = (new_imageX[i+1, j+1]*new_imageX[i+1,j+1] + new_imageY[i+1, j+1]*new_imageY[i+1,j+1])**0.5

# return np.uint8(new_imageX)

# return np.uint8(new_imageY)

return np.uint8(new_image) # 无方向算子处理的图像

# Laplace算子

# 常用的Laplace算子模板 [[0,1,0],[1,-4,1],[0,1,0]] [[1,1,1],[1,-8,1],[1,1,1]]

def Laplace_suanzi(img):

r, c = img.shape

new_image = np.zeros((r, c))

L_sunnzi = np.array([[0,-1,0],[-1,4,-1],[0,-1,0]])

# L_sunnzi = np.array([[1,1,1],[1,-8,1],[1,1,1]])

for i in range(r-2):

for j in range(c-2):

new_image[i+1, j+1] = abs(np.sum(img[i:i+3, j:j+3] * L_sunnzi))

return np.uint8(new_image)

#反色函数

def inverse_color(img):

height,width = img.shape

img2 = img.copy()

for i in range(height):

for j in range(width):

img2[i,j] = (255-img[i,j])

return img2

img = cv2.imread('E:/test3.bmp', cv2.IMREAD_GRAYSCALE)

cv2.imshow('image', img)

img2 = inverse_color(img)

cv2.imshow('image2',img2)

# # robers算子

out_robert = robert_suanzi(img)

out_robert = inverse_color(out_robert)

cv2.imshow('robert_image', out_robert)

# sobel 算子

out_sobel = sobel_suanzi(img)

out_sobel = inverse_color(out_sobel)

cv2.imshow('sobel_image', out_sobel)

# Laplace算子

out_laplace = Laplace_suanzi(img)

out_laplace = inverse_color(out_laplace)

cv2.imshow('laplace_image', out_laplace)

cv2.waitKey(0)

cv2.destroyAllWindows()

二、运行效果

原图