OpenCV Python can't use SURF, SIFT
Question: I'm trying a simple thing like

    
    
        detector = cv2.SIFT()
    

and get this bad error

    
    
    detector = cv2.SIFT()
    AttributeError: 'module' object has no attribute 'SIFT'
    

I do not understand that because cv2 is installed.

cv2.**version** is

    
    
    $Rev: 4557 $
    

my system is Ubuntu 12.04

maybe someone has got the same problem and could help me

thanks a lot

EDIT*:

long story short testypypypy.py

    
    
    import cv2
    
    detector = cv2.SIFT()
    

ERROR

    
    
    Traceback (most recent call last):
      File "testypypy.py", line 3, in <module>
        detector = cv2.SIFT()
    AttributeError: 'module' object has no attribute 'SIFT
    

if i take "SURF" it works because SURF is in dir(cv2) but if i also take
cv2.BFMatcher() i get the same error...so it's missing and i have to add it
but i don't know how


Answer: FYI, as of 3.0.0 SIFT and friends are in a contrib repo located at
<https://github.com/Itseez/opencv_contrib> and are not included with opencv by
default.

