Computer vision is a relatively young branch of computer science, so many famous algorithms and techniques have only been invented recently. SIFT is, in fact, only 21 years old, having been published by David Lowe in 1999.
SURF is a feature detection algorithm that was published in 2006 by Herbert Bay. SURF is several times faster than SIFT, and it is partially inspired by it.
Note that both SIFT and SURF are patented algorithms and, for this reason, are made available only in builds of opencv_contrib where the OPENCV_ENABLE_NONFREE CMake flag is used.
It is not particularly relevant to this book to understand how SURF works under the hood, inasmuch as we can use it in our applications and make the best of it. What is important to understand is that cv2.SURF is an OpenCV class that performs keypoint detection with...
