1 | initial version |
To best of my understanding after looking at the code I found under opencv\sources\modules\imgproc\src\hough.cpp ->icvHoughCirclesGradient OpenCV uses gradient information to reduce voting a full cirlce to only two votes for each edges points. This explains part of the speed up.
After implementing my own version that uses gradient information I am "only" 100 times slower than OpenCVs version.