在 hough 函数中传递 math.pi（pi 数）的原因是什么？

Question

我不知道在 hough 函数中传递阈值数字的原因

cv.HoughLines(src, lines, 1, Math.PI / 180, 30, 0, 0, 0);

Answer 1

Based on OpenCV's documentation here :

HoughLines(InputArray image, OutputArray lines, double rho, double theta, int threshold, double srn=0, double stn=0 )

the fourth parameter is theta which refers to:

theta – Angle resolution of the accumulator in radians .

In order to convert d degrees to radians, you should multiply d by Math.Pi and divide it by 180. In your example, the angle resolution is set to 1 degree or Math.Pi / 180 radians.