使用OpenCV 2.4.9检测矩形

Question

I want to detect rectangles from an image, and this is the code I am using:

    import cv2 ; import numpy as np
    img = cv2.imread('/home/stagiaire/Bureau/new_photos_mire/0294/new/corrigees/GRE.TIF',0)
ret,thresh = cv2.threshold(img,127,255,0)
    contours,hierarchy = cv2.findContours(thresh, 1, 2)
    cnt = contours[0]
    x,y,w,h = cv2.boundingRect(cnt)
    cv2.rectangle(img,(x,y),(x+w,y+h),(0,255,0),2)

    rect = cv2.minAreaRect(cnt)
    box = cv2.boxPoints(rect)
    box = np.int0(box)
    im = cv2.drawContours(im,[box],0,(0,0,255),2)

The message error I am getting is:

AttributeError: 'module' object has no attribute 'boxPoints'

Concerning this line of code:

    box = cv2.boxPoints(rect)

I beleive that it is caused because of the version of OpenCV I am using (2.4.9). It is not possible for me now to have the 3.0 version so any way I can detect rectangles using openCV 2.9 and Python 2.7 ??

EDIT

So as answered by Surabhi Valma, this could be a solution :

Just add cv2.cv.BoxPoints(rect) instead of cv2.boxPoints(rect)

Answer 1

When I go thru releases could not find 2.9. May be your version is 2.4.9. If you try with 3.x, it may work.

There was an opencv-issue / feature already tracked to closure This function is for sure available in 3.0.0-dev or above, Please try to upgrade and check.

Answer 2

The most recent OpenCV 2 release is 2.4.13.2; there is no 2.9. Anyways, this method was never included in the cv2 library with Python wrappers. Your choices are to upgrade to OpenCV 3+ or fall back on the (deprecated) cv module (which is included with older versions of Python OpenCV wrappers) to access the C method directly:

rect = cv2.minAreaRect(cnt)
box = np.int0(cv2.cv.BoxPoints(rect))
cv2.drawContours(im,[box],0,(0,0,255),2)

Answer 3

只需添加cv2.cv.BoxPoints(rect)而不是cv2.boxPoints(rect)