How to implement a gradient based Hough transform

1. What is Hough gradient?
2. Can Hough transform detect curved lines?
3. How can Hough transform be used to identify lines?

What is Hough gradient?

In case of HOUGH_GRADIENT , it is the higher threshold of the two passed to the Canny edge detector (the lower one is twice smaller). param2. second method-specific parameter. In case of HOUGH_GRADIENT , it is the accumulator threshold for the circle centers at the detection stage.

Can Hough transform detect curved lines?

The Hough Transform (HT) is a popular technique for detecting straight lines and curves on gray-scale images. It maps image data from image space to a parameter space, where curve detection becomes peak detection problem.

How can Hough transform be used to identify lines?

If two edge points lay on the same line, their corresponding cosine curves will intersect each other on a specific (ρ, θ) pair. Thus, the Hough Transform algorithm detects lines by finding the (ρ, θ) pairs that have a number of intersections larger than a certain threshold.