Adding modules from opencv_contrib to OpenCV

Question

I\'m trying to add the xfeatures2d module from opencv_contrib to an existing OpenCV/Python project.

I\'ve downloaded the latest version of

Answer 1

you are missing the new, additional namespace:

---

>>> help(cv2.xfeatures2d)
Help on module cv2.xfeatures2d in cv2:

NAME
    cv2.xfeatures2d

FILE
    (built-in)

FUNCTIONS
    SIFT(...)
        SIFT([, nfeatures[, nOctaveLayers[, contrastThreshold[, edgeThreshold[,
sigma]]]]]) -> <xfeatures2d_SIFT object>

    SURF(...)
        SURF([hessianThreshold[, nOctaves[, nOctaveLayers[, extended[, upright]]
]]]) -> <xfeatures2d_SURF object>

    StarDetector(...)
        StarDetector([, _maxSize[, _responseThreshold[, _lineThresholdProjected[
, _lineThresholdBinarized[, _suppressNonmaxSize]]]]]) -> <xfeatures2d_StarDetect
or object>

DATA
    FREAK_NB_ORIENPAIRS = 45
    FREAK_NB_PAIRS = 512
    FREAK_NB_SCALES = 64


>>> surf = cv2.xfeatures2d.SURF(300)

Answer 2

I encountered this same issue. I'm using python 2.7.6 and OpenCv 3.0 with the additional non-free modules. I do have xfeatures2d present in available modules and can import it, however it was as though xfeatures2d didn't contain SIFT or SURF. No matter how I called them it was the same Error:

"AttributeError: 'module' object has no attribute 'SIFT'

I tried the different name spaces suggested, and only recently noticed this detail and GOT IT WORKING!

$ python

>>>import cv2

>>>help(cv2.xfeatures2d)

You'll notice that it replies that it is now referred to as...

FUNCTIONS

SIFT_create(...)

and

SURF_create(...)

So very simply - the namespace is NOT "cv2.SIFT()" or "cv2.xfeatures2d.SIFT" but rather

cv2.xfeatures2d.SIFT_create()

Please give it a shot!

Answer 3

Another possibility (and the easiest one I found!) is to install the 2.4.9 release which already include SIFT and SURF algorithm. You just have to do then

import cv2
sift = cv2.SIFT()
(...)

Answer 4

Install it from pip

Python 2.x

pip install opencv-contrib-python

Python 3.x

pip3 install opencv-contrib-python

Use sudo if a permsision error occurred.