'module' object has no object 'drawMatchesKnn'

Question

I am using python 2.7. An error arose while matching features:

"'module' object has no object 'drawMatchesKnn'"

What does this error mean and how do I resolve it? I am using numpy, cv2 and matplotlib.

The program is a FLANN based matcher:

import numpy as np
import cv2
from matplotlib import pyplot as plt

img1 = cv2.imread('1_1.jpg',0)          # queryImage
img2 = cv2.imread('1.jpg',0) # trainImage

# Initiate SIFT detector
sift = cv2.SIFT()

# find the keypoints and descriptors with SIFT
kp1, des1 = sift.detectAndCompute(img1,None)
kp2, des2 = sift.detectAndCompute(img2,None)

# FLANN parameters
FLANN_INDEX_KDTREE = 0
index_params = dict(algorithm = FLANN_INDEX_KDTREE, trees = 5)
search_params = dict(checks=50)   # or pass empty dictionary

flann = cv2.FlannBasedMatcher(index_params,search_params)

matches = flann.knnMatch(des1,des2,k=2)

# Need to draw only good matches, so create a mask
matchesMask = [[0,0] for i in xrange(len(matches))]

# ratio test as per Lowe's paper
for i,(m,n) in enumerate(matches):
    if m.distance < 0.7*n.distance:
        matchesMask[i]=[1,0]

draw_params = dict(matchColor = (0,255,0),
                   singlePointColor = (255,0,0),
                   matchesMask = matchesMask,
                   flags = 0)

img3 = cv2.drawMatchesKnn(img1,kp1,img2,kp2,matches,None,**draw_params)

plt.imshow(img3,),plt.show()

Answer 1

错误告诉您cv2模块没有对象drawMatchesKnn。我认为这是版本问题，您应该确保使用的是cv2版本3.0。