You can try morphological closing.
Python code:
# -*- coding: utf-8 -*-
import qrtools
import cv2
import numpy as np
imgPath = "Fdnm1.png"
img = cv2.imread(imgPath, 0)
kernel = np.ones((5, 5), np.uint8)
processed=cv2.morphologyEx(img, cv2.MORPH_CLOSE, kernel)
cv2.imwrite('test.png', processed)
d = qrtools.QR(filename='test.png')
d.decode()
print d.data
Result:
1MB24