mnist有多少张图片(怎么读取图片文字)

#读取文件夹mnist下的60000张图片，图片为灰度图，所以为1通道，如果是将彩色图作为输入,则将1替换为3,图像大小28*28
def load_data():
	data = np.empty((60000,1,28,28),dtype="float32")
	label = np.empty((60000,),dtype="uint8")
	imgs = os.listdir("E:\\DataSet\\mnist")
	num = len(imgs)
	for i in range(num):
		img = Image.open("E:\\DataSet\\mnist\\"+imgs[i])
		arr = np.asarray(img,dtype="float32")
		data[i,:,:,:] = arr
		label[i] = int(imgs[i].split('.')[0])
	#归一化和零均值化
	data /= np.max(data)
	data -= np.mean(data)
	return data,label

if __name__ == '__main__':
	load_data()

from keras.datasets import mnist

(X_train, y_train), (X_test, y_test) = mnist.load_data()