我试图从python中的opencv 3访问SIFT和SURF功能 . 正如其他人所建议的那样，我遵循了opencv_contrib的安装 . 安装的一些日志是：
[ 82%] Built target opencv_xfeatures2d
...
Installing: /usr/local/lib/libopencv_xfeatures2d.so
-- Set runtime path of "/usr/local/lib/libopencv_xfeatures2d.so.3.0.0" to "/usr/local/lib"
-- Installing: /usr/local/include/opencv2/xfeatures2d.hpp
-- Installing: /usr/local/include/opencv2/xfeatures2d/cuda.hpp
-- Installing: /usr/local/include/opencv2/xfeatures2d/nonfree.hpp
之后我在python中导入cv2但无法导入xfeatures2d .
>>> import cv2
>>> cv2.xfeatures2d.SIFT_create()
Traceback (most recent call last):
File "<stdin>", line 1, in <module>
AttributeError: 'module' object has no attribute 'xfeatures2d'
任何线索？