python如何读jpg文件

from PIL import Image

import numpy as np

I = Image.open('./cc_1.png')

I.show()   

I.save('./save.png')

I_array = np.array(I)

print I_array.shape

import matplotlib.pyplot as plt

import matplotlib.image as mpimg

import numpy as np

I = mpimg.imread('./cc_1.png')

print I.shape

plt.imshow(I)

import cv2

I = cv2.imread('./cc_1.png')

print I.shape