Python实现计算图像RGB均值,怎么只读一张图片？

Question

网上用python实现计算图像RGB均值都是批量的，而我只想得到一张图片的rgb均值（即整张图片三个通道的三个均值）如下的代码是一位大神的代码，对于刚学python的小白不会修改，求大神帮助。总之就是将下面代码从批量变为只分析一张图片的。问题应该简单，原谅我的无知。这是源码地址：https://blog.csdn.net/yql_617540298/article/details/83617512

-*- coding: utf-8 -*-

"""
Created on Thu Nov 1 10:43:29 2018
@author: Administrator
"""

import os
import cv2
import numpy as np

path = 'C:/Users/Administrator/Desktop/rgb'
def compute(path):
file_names = os.listdir(path)
per_image_Rmean = []
per_image_Gmean = []
per_image_Bmean = []
for file_name in file_names:
img = cv2.imread(os.path.join(path, file_name), 1)
per_image_Bmean.append(np.mean(img[:,:,0]))
per_image_Gmean.append(np.mean(img[:,:,1]))
per_image_Rmean.append(np.mean(img[:,:,2]))
R_mean = np.mean(per_image_Rmean)
G_mean = np.mean(per_image_Gmean)
B_mean = np.mean(per_image_Bmean)
return R_mean, G_mean, B_mean

if name == '__main__':
R, G, B= compute(path)
print(R, G ,B)

Answer 1

path = '16.png'
def compute(path):

image_Rmean = []
image_Gmean = []
image_Bmean = []
img = cv2.imread(path, 1)
image_Bmean.append(np.mean(img[:,:,0]))
image_Gmean.append(np.mean(img[:,:,1]))
image_Rmean.append(np.mean(img[:,:,2]))
R_mean = np.mean(image_Rmean)
G_mean = np.mean(image_Gmean)
B_mean = np.mean(image_Bmean)
return R_mean, G_mean, B_mean

if name == '__main__':
R, G, B= compute(path)
Y = 0.299*R+0.587*G+0.114*B
print("目标图片亮度为"+str(round(Y,2)))