14、OpenCV Python 直线检测

 1 __author__ = "WSX"
 2 import cv2 as cv
 3 import numpy as np
 4 #-----------------霍夫变换---------------------
 5 #前提条件： 边缘检测完成
 6 def line_detection(image):
 7     gray = cv.cvtColor(image, cv.COLOR_BGR2GRAY)
 8     edges = cv.Canny(gray, 50, 150, apertureSize=3)
 9     lines = cv.HoughLines(edges, 1, np.pi/180, 200)
10     for line in lines:
11         print(type(lines))
12         rho, theta = line[0]
13         a = np.cos(theta)
14         b = np.sin(theta)
15         x0 = a * rho
16         y0 = b * rho
17         x1 = int(x0+1000*(-b))
18         y1 = int(y0+1000*(a))
19         x2 = int(x0-1000*(-b))
20         y2 = int(y0-1000*(a))
21         cv.line(image, (x1, y1), (x2, y2), (0, 0, 255), 2)
22     cv.imshow("image-lines", image)
23 
24 
25 def line_detect_possible_demo(image):
26     gray = cv.cvtColor(image, cv.COLOR_BGR2GRAY)
27     edges = cv.Canny(gray, 50, 150, apertureSize=3)
28     lines = cv.HoughLinesP(edges, 1, np.pi/180, 100, minLineLength=50, maxLineGap=10)
29     for line in lines:
30         print(type(line))
31         x1, y1, x2, y2 = line[0]
32         cv.line(image, (x1, y1), (x2, y2), (0, 0, 255), 2)
33     cv.imshow("line_detect_possible_demo", image)
34 
35 def main():
36     img = cv.imread("1.JPG")
37     cv.namedWindow("Show", cv.WINDOW_AUTOSIZE)
38     cv.imshow("Show", img)
39     line_detect_possible_demo(img)
40 
41     cv.waitKey(0)
42     cv.destroyAllWindows()
43 
44 main()