python - 无法在 python OpenCV 绑定中导入 xfeatures2d

Question

我正在尝试从 python 中的 opencv 3 访问 SIFT 和 SURF 功能。按照其他人的建议，我跟着opencv_contrib的安装。一些安装日志如下：

[ 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'

有什么线索吗？