Python imread、newaxis用法详解

import cv2
path = 'E:\Flow classification\email_train1.jpg'
image = cv2.imread(path)
print(image)
print(type(image))

import numpy as np
 
a=np.array([1,2,3,4,5,6,7,8,9])
print(a.shape)
print(a)
 
b = a[:,np.newaxis]
print(b.shape)
print(b)
 
c = b[:,:,np.newaxis]
print(c.shape)
print(c)
 
d = c[:,:,:,np.newaxis]
print(d.shape)
print(d)

(9,)
[1 2 3 4 5 6 7 8 9]

(9, 1)
[[1]
 [2]
 [3]
 [4]
 [5]
 [6]
 [7]
 [8]
 [9]]

(9, 1, 1)
[[[1]]

 [[2]]

 [[3]]

 [[4]]

 [[5]]

 [[6]]

 [[7]]

 [[8]]

 [[9]]]

(9, 1, 1, 1)
[[[[1]]]

 [[[2]]]

 [[[3]]]

 [[[4]]]

 [[[5]]]

 [[[6]]]

 [[[7]]]

 [[[8]]]

 [[[9]]]]