data.py

#coding:utf-8
"""
Author:wepon
Source:https://github.com/wepe

"""


import os
from PIL import Image
import numpy as np

#读取文件夹mnist下的42000张图片，图片为灰度图，所以为1通道，图像大小28*28
#如果是将彩色图作为输入,则将1替换为3，并且data[i,:,:,:] = arr改为data[i,:,:,:] = [arr[:,:,0],arr[:,:,1],arr[:,:,2]]
def load_data():
	data = np.empty((42000,1,28,28),dtype="float32")
	label = np.empty((42000,),dtype="uint8")

	imgs = os.listdir("./mnist")
	num = len(imgs)
	for i in range(num):
		img = Image.open("./mnist/"+imgs[i])
		arr = np.asarray(img,dtype="float32")
		data[i,:,:,:] = arr
		label[i] = int(imgs[i].split('.')[0])
        data /= np.max(data)
        data -= np.mean(data)
	return data,label