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import os from PIL import Image import matplotlib.pyplot as plt import numpy as np from scipy.misc import imread filepath = '/home/JPEGImages' # 數據集目錄 pathDir = os.listdir(filepath)R_channel = 0 G_channel = 0 B_channel = 0 for idx in xrange(len(pathDir)):filename = pathDir[idx]img = imread(os.path.join(filepath, filename))R_channel = R_channel + np.sum(img[:,:,0])G_channel = G_channel + np.sum(img[:,:,1])B_channel = B_channel + np.sum(img[:,:,2])num = len(pathDir) * 384 * 512 # 這里（384,512）是每幅圖片的大小，所有圖片尺寸都一樣 R_mean = R_channel / num G_mean = G_channel / num B_mean = B_channel / num
R_channel = 0 G_channel = 0 B_channel = 0 for idx in xrange(len(pathDir)):filename = pathDir[idx]img = imread(os.path.join(filepath, filename))R_channel = R_channel + np.sum((img[:,:,0] - R_mean)**2)G_channel = G_channel + np.sum((img[:,:,1] - G_mean)**2)B_channel = B_channel + np.sum((img[:,:,2] - B_mean)**2) R_var = R_channel / num G_var = G_channel / num B_var = B_channel / num print("R_mean is %f, G_mean is %f, B_mean is %f" % (R_mean, G_mean, B_mean)) print("R_var is %f, G_var is %f, B_var is %f" % (R_var, G_var, B_var))

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轉載于:https://www.cnblogs.com/jiangkejie/p/10104232.html

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