14、OpenCV Python 直线检测

 __author__ = "WSX"
 import cv2 as cv
 import numpy as np
 #-----------------霍夫变换---------------------
 #前提条件： 边缘检测完成
 def line_detection(image):
     gray = cv.cvtColor(image, cv.COLOR_BGR2GRAY)
     edges = cv.Canny(gray, 50, 150, apertureSize=3)
     lines = cv.HoughLines(edges, 1, np.pi/180, 200)
     for line in lines:
         print(type(lines))
         rho, theta = line[0]
         a = np.cos(theta)
         b = np.sin(theta)
         x0 = a * rho
         y0 = b * rho
         x1 = int(x0+1000*(-b))
         y1 = int(y0+1000*(a))
         x2 = int(x0-1000*(-b))
         y2 = int(y0-1000*(a))
         cv.line(image, (x1, y1), (x2, y2), (0, 0, 255), 2)
     cv.imshow("image-lines", image)

 def line_detect_possible_demo(image):
     gray = cv.cvtColor(image, cv.COLOR_BGR2GRAY)
     edges = cv.Canny(gray, 50, 150, apertureSize=3)
     lines = cv.HoughLinesP(edges, 1, np.pi/180, 100, minLineLength=50, maxLineGap=10)
     for line in lines:
         print(type(line))
         x1, y1, x2, y2 = line[0]
         cv.line(image, (x1, y1), (x2, y2), (0, 0, 255), 2)
     cv.imshow("line_detect_possible_demo", image)

 def main():
     img = cv.imread("1.JPG")
     cv.namedWindow("Show", cv.WINDOW_AUTOSIZE)
     cv.imshow("Show", img)
     line_detect_possible_demo(img)

     cv.waitKey(0)
     cv.destroyAllWindows()

 main()