#coding:utf-8
#第一种方式 很慢很慢 自己写的如何计算均值
'''
import cv2
import os
def access_pixels(frame):
print(frame.shape) #shape内包含三个元素：按顺序为高、宽、通道数
height = frame.shape[0]
weight = frame.shape[1]
channels = frame.shape[2]
value_b = 0
value_g = 0
value_r = 0
print("weight : %s, height : %s, channel : %s" %(weight, height, channels))
for row in range(height): #遍历高
for col in range(weight): #遍历宽
value_b = value_b + frame[row, col, 0]
value_g = value_g + frame[row, col, 1]
value_r = value_r + frame[row, col, 2]
singlePicValue_b = value_b / (height * weight)
singlePicValue_g = value_g / (height * weight)
singlePicValue_r = value_r / (height * weight)
return singlePicValue_b,singlePicValue_g,singlePicValue_r
def computeMeanValue(path):
imgList1 = os.listdir(path)
mean_b = 0
mean_g = 0
mean_r = 0
for i in range(len(imgList1)):
srcframe = cv2.imread(os.path.join(path,imgList1[i]))
singlePicValue_b,singlePicValue_g,singlePicValue_r = access_pixels(srcframe)
mean_b = mean_b + singlePicValue_b
mean_g = mean_g + singlePicValue_g
mean_r = mean_r + singlePicValue_r
all_mean_b = mean_b / len(imgList1)
all_mean_g = mean_g / len(imgList1)
all_mean_r = mean_r / len(imgList1)
print (i)
return all_mean_b,all_mean_g,all_mean_r
all_mean_b,all_mean_g,all_mean_r = computeMeanValue('./spinningData/src')
print (all_mean_b,all_mean_g,all_mean_r)
'''
#第二种方式 借助numpy 很快 几秒
import os
import cv2
import numpy as np
path = './spinningData/src'
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)
