* Error Message for SURF if not implemented
In OpenCV 4.5.1
import cv2 as cv
cv.xfeatures2d_SURF.create
will not create an AttributeError, even if the function is excluded (no nonfree option)
In Line 305 (now 306) however ´finder = FEATURES_FIND_CHOICES[args.features]()´ will raise an
error: OpenCV(4.5.1) ..\opencv_contrib\modules\xfeatures2d\src\surf.cpp:1029: error: (-213:The function/feature is not implemented) This algorithm is patented and is excluded in this configuration; Set OPENCV_ENABLE_NONFREE CMake option and rebuild the library in function 'cv::xfeatures2d::SURF::create'
So we should check with cv.xfeatures2d_SURF.create() correctly if SURF is available
Lukas-Alexander Weber
7c4b873ba3