img = cv2.imread(‘pie.png‘,cv2.IMREAD_GRAYSCALE) cv2.imshow("img",img) cv2.waitKey() cv2.destroyAllWindows()
效果：
ddepth:图像的深度
dx和dy分别表示水平和竖直方向
ksize是Sobel算子的大小
def cv_show(img,name): cv2.imshow(name,img) cv2.waitKey() cv2.destroyAllWindows() sobelx = cv2.Sobel(img,cv2.CV_64F,1,0,ksize=3) cv_show(sobelx,‘sobelx‘)
效果：
sobelx = cv2.Sobel(img,cv2.CV_64F,1,0,ksize=3) sobelx = cv2.convertScaleAbs(sobelx) #白到黑是正数，黑到白就是负数了，所有的负数会被截断成0，所以要取绝对值 cv_show(sobelx,‘sobelx‘)
效果：
sobely = cv2.Sobel(img,cv2.CV_64F,0,1,ksize=3) sobely = cv2.convertScaleAbs(sobely) cv_show(sobely,‘sobely‘)
效果：
sobelxy = cv2.addWeighted(sobelx,0.5,sobely,0.5,0) #分别计算x和y，再求和的结果 cv_show(sobelxy,‘sobelxy‘)
效果：
sobelxy=cv2.Sobel(img,cv2.CV_64F,1,1,ksize=3) #直接计算的效果，不是很好 sobelxy = cv2.convertScaleAbs(sobelxy) cv_show(sobelxy,‘sobelxy‘)
效果：
img = cv2.imread(‘lena.jpg‘,cv2.IMREAD_GRAYSCALE) cv_show(img,‘img‘)
效果：
img = cv2.imread(‘lena.jpg‘,cv2.IMREAD_GRAYSCALE) sobelx = cv2.Sobel(img,cv2.CV_64F,1,0,ksize=3) sobelx = cv2.convertScaleAbs(sobelx) sobely = cv2.Sobel(img,cv2.CV_64F,0,1,ksize=3) sobely = cv2.convertScaleAbs(sobely) sobelxy = cv2.addWeighted(sobelx,0.5,sobely,0.5,0) cv_show(sobelxy,‘sobelxy‘)
效果：
img = cv2.imread(‘lena.jpg‘,cv2.IMREAD_GRAYSCALE) sobelxy=cv2.Sobel(img,cv2.CV_64F,1,1,ksize=3) sobelxy = cv2.convertScaleAbs(sobelxy) cv_show(sobelxy,‘sobelxy‘)
效果：
Scharr算子Gy右边的-3改为3
laplacian算子
#不同算子的差异 img = cv2.imread(‘lena.jpg‘,cv2.IMREAD_GRAYSCALE) sobelx = cv2.Sobel(img,cv2.CV_64F,1,0,ksize=3) sobely = cv2.Sobel(img,cv2.CV_64F,0,1,ksize=3) sobelx = cv2.convertScaleAbs(sobelx) sobely = cv2.convertScaleAbs(sobely) sobelxy = cv2.addWeighted(sobelx,0.5,sobely,0.5,0) scharrx = cv2.Scharr(img,cv2.CV_64F,1,0) scharry = cv2.Scharr(img,cv2.CV_64F,0,1) scharrx = cv2.convertScaleAbs(scharrx) scharry = cv2.convertScaleAbs(scharry) scharrxy = cv2.addWeighted(scharrx,0.5,scharry,0.5,0) laplacian = cv2.Laplacian(img,cv2.CV_64F) laplacian = cv2.convertScaleAbs(laplacian) res = np.hstack((sobelxy,scharrxy,laplacian)) cv_show(res,‘res‘)
效果：
原文：https://www.cnblogs.com/SCCQ/p/12291183.html