python - OpenCV:像素数与行数*列数

Question

我运行以下代码:

import cv2
import numpy as np 

img_file='pokemon.jpg'
img=cv2.imread(img_file)  

# print total number of rows, columns and channels that are provided in the picture
print 'Image shape: ',img.shape # rows = 630, columns = 900

# now let us print the total number of pixels that the picture has 
print 'Number of pixels: ', img.size # 1701000
print 630*900 # 56700

为什么最后两个输出不同？代表像素矩阵内组织的像素数量的列数和行数不是吗？

Answer 1

感谢@beaker的评论，答案是:

For multichannel images the columns contain as many sub columns as the number of channels. For example in case of an RGB color system:

Documentation.