There is some thing i dont understand about Hough Transform in polar coordinates.
From wikipedia article:
"The simplest case of Hough transform is detecting straight lines. In general, the straight line y = mx + b can be represented as a point (b, m) in the parameter space. However, vertical lines pose a problem. They would give rise to unbounded values of the slope parameter m. Thus, for computational reasons, Duda and Hart[5] proposed the use of the Hesse normal form $R = X*Cos(\theta) + Y*Sin(\theta)$ , where $R$ is the distance from the origin to the closest point on the straight line, and $\theta$ is the angle between the x axis and the line connecting the origin with that closest point."
now the issue im having with this is:
The Distance from the origin to the closest point on the straight line would be
$\sqrt{x^2 + y^2}$ by the euclidean metric
and not
$R = X*Cos(\theta) + Y*Sin(\theta)$