为python安装带有额外模块（sift、surf…）的OpenCV 3.0

Question

我试着用额外的软件包（sift，surf…）安装（很多次）OpenCV 3.0 for python，但总是失败，我真的被卡住了。 我在主环境中试过，然后在虚拟环境中试过

以下是我所做的：

cd git
git clone https://github.com/Itseez/opencv_contrib.git
cd ..
wget https://github.com/Itseez/opencv/archive/3.0.0-beta.zip
unzip 3.0.0-beta.zip
cd opencv-3.0.0-beta/
mkdir release
cd release/
workon OCR
cmake -D CMAKE_BUILD_TYPE=Release -D CMAKE_INSTALL_PREFIX=/home/jbd/src/opencv-3.0.0b -D OPENCV_EXTRA_MODULES_PATH=/home/jbd/git/opencv_contrib/modules -D BUILD_opencv_python3=ON -D PYTHON2_EXECUTABLE=/home/jbd/.virtualenv/OCR/bin/python -D PYTHON_INCLUDE_DIR=/home/jbd/.virtualenv/OCR/include/python2.7 -D PYTHON_LIBRARY=/usr/lib/libpython2.7.so -D PYTHON2_NUMPY_INCLUDE_DIRS=/home/jbd/.virtualenv/OCR/local/lib/python2.7/site-packages/numpy ..
make -j7
make install
cd ~/.virtualenv/OCR/lib/python2.7/site-packages/
ln -s /home/jbd/src/opencv-3.0.0b/lib/python2.7/site-packages/cv2.so

不管我用什么方法安装它，我总是得到：

Traceback (most recent call last): File "/home/jbd/git/ocr/test.py", line 10, in sift = cv2.xfeatures2d.SIFT() AttributeError: 'module' object has no attribute 'SIFT'

使用：

import numpy as np
import cv2
sift = cv2.xfeatures2d.SIFT()

如果有人知道我错在哪里。。。

非常感谢

Answer 1

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

NAME
    cv2.xfeatures2d

FILE
    (built-in)

FUNCTIONS
    SIFT_create(...)
        SIFT_create([,nfeatures[,nOctaveLayers[,contrastThreshold[,edgeThreshold[,sigma]]]]) -> retval

    SURF_create(...)
        SURF_create([,hessianThreshold[,nOctaves[,nOctaveLayers[,extended[,upright]]]]]) -> retval

---

使用opencv3.0，您必须使用XXXX_create()函数来获取实例 所以，它是：

orb = cv2.ORB_create()

以及：

sift = cv2.xfeatures2d.SIFT_create()
sift.detect(...)
sift.compute(...)