报错:TypeError: ‘NoneType’ object is not iterable
原因:阈值过高导致lines=None,也就是说输入的图片很难检测到直线
def line_image(image):
gray = cv.cvtColor(image, cv.COLOR_RGB2GRAY)
edges = cv.Canny(gray, 50, 150, apertureSize=3)
lines = cv.HoughLines(edges, 1, np.pi/180, 200)
for line in 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("line", image)
src = cv.imread('./static/image/cut1.jpg')
cv.imshow('image', src)
line_image(src)
cv.waitKey(0)
cv.destroyAllWindows()
效果如下: