This package performs Hough transform on binary images. The transform is from the x-y image space to the xc-yc-r parameter space, where (xc,yc) is the center of the circle, and r is the radius.
The package can also find the best fit of a circle in the binary image. This is done by performing 3D Gaussian filtering in the xc-yc-r 3D parameter space.
The core algorithm is written in C++, thus is very fast. You need Matlab compiler to compile it.