def match(desc1,desc2,threshold=0.5):

n = len(desc1[0])

d = -ones((len(desc1),len(desc2)))
for i in range(len(desc1)):
 for j in range(len(desc2)):
  d1 = (desc1[i] - mean(desc1[i])) / std(desc1[i])
  d2 = (desc2[j] - mean(desc2[j])) / std(desc2[j])
  ncc_value = sum(d1 * d2) / (n-1)
  if ncc_value > threshold:
   d[i,j] = ncc_value
ndx = argsort(-d)
matchscores = ndx[:,0]
return matchscores