Python图片与其矩阵数据互相转换

# coding=gbk
from PIL import Image
import numpy as np
# import scipy
import matplotlib.pyplot as plt

def ImageToMatrix(filename):
    # 读取图片
    im = Image.open(filename)
    # 显示图片
#     im.show()  
    width,height = im.size
    im = im.convert("L") 
    data = im.getdata()
    data = np.matrix(data,dtype=‘float‘)/255.0
    new_data = np.reshape(data,(width,height))
    return new_data
#     new_im = Image.fromarray(new_data)
#     # 显示图片
#     new_im.show()
def MatrixToImage(data):
    data = data*255
    new_im = Image.fromarray(data.astype(np.uint8))
    return new_im
    
    

filename = ‘lena.jpg‘
data = ImageToMatrix(filename)
print data 
new_im = MatrixToImage(data)
plt.imshow(data, cmap=plt.cm.gray, interpolation=‘nearest‘)
new_im.show()
new_im.save(‘lena_1.bmp‘)