opencv 检测图像线条 霍夫线检测

Posted 2021-03-04 wojianxin

 1 # Writer : [e-mail]
 2 
 3 # Data  : 2020.3.21
 4 
 5 import cv2 as cv
 6 
 7 import numpy as np
 8 
 9 img = cv.imread(‘../paojie.jpg‘)
10 
11 gray = cv.cvtColor(img,cv.COLOR_BGR2GRAY)
12 
13 # 50,150 为二值化时的阈值 apertureSize为Sobel滤波器的大小
14 
15 edges = cv.Canny(gray,50,150,apertureSize = 3)
16 
17 cv.imshow(‘Canny Result‘,edges)
18 
19 cv.imwrite(‘Canny_Result.jpg‘,edges)
20 
21 # 高效的霍夫线检测算法
22 
23 # edges ： 二值图像
24 
25 # 1    ： ρ
26 
27 # pi/180： θ
28 
29 # 100  ： Accumulator threshold parameter. Only those lines are returned that get enough votes ( >threshold ).
30 
31 # minLineLength ： Minimum length of line. Line segments shorter than this are rejected.
32 
33 # maxLineGap    ： Maximum allowed gap between line segments to treat them as a single line.
34 
35 lines = cv.HoughLinesP(edges,1,np.pi/180,100,minLineLength=100,maxLineGap=10)
36 
37 for line in lines:
38 
39     x1,y1,x2,y2 = line[0]
40 
41     cv.line(img,(x1,y1),(x2,y2),(0,255,0),2)
42 
43 cv.imshow(‘HoughLines Result‘,img)
44 
45 cv.imwrite(‘HoughLines_Result.jpg‘,img)
46 
47 cv.waitKey(0)
48 
49 cv.destroyAllWindows()

 

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原图 ↑

 

Canny_Result.jpg ↑

 

HoughLines_Result.jpg ↑