[Numpy] RGB mean/std 구하기

import json 
from PIL import Image
import numpy as np

with open('test.json', 'r') as json_file:
    dataset = json.load(json_file)

print(len(dataset))

images = []
i = 0
for k, v in dataset.items():
    i += 1
    print(i, k)

    image = Image.open(k)
    image = np.asarray(image)
    images.append(image)

images = np.array(images)

print("MEAN")
print(np.mean(images[:,:,:,0]) / 255.)
print(np.mean(images[:,:,:,1]) / 255.)
print(np.mean(images[:,:,:,2]) / 255.)

print("STD")
print(np.std(images[:,:,:,0]) / 255.)
print(np.std(images[:,:,:,1]) / 255.)
print(np.std(images[:,:,:,2]) / 255.)