cv2对图像进行反向处理，显示高度超纲怎么办？axis 0

Question

源代码：

import cv2 as cv
import numpy as num

def access_pixels(image):
    print(image.shape)
    height=image.shape[0]
    width=image.shape[1]
    channels=image.shape[2]
    print('height:%s width:%s channels:%s'%(height,width,channels))
    for row in range(height):
        for col in range(width):
            for c in range(channels):
                pv=image[height,width,channels]
                image[row,col,c]= 255 - pv
    cv.imshow('pixels_demo',image)

src=cv.imread('D:\girl.jpg')
src1=cv.resize(src,(1,200),)
cv.namedWindow('input image',cv.WINDOW_AUTOSIZE)
cv.imshow('input image',src1)
access_pixels(src1)
cv.waitKey(0)
cv.destroyAllWindows()

运行后，出现的问题：

C:\ProgramData\Anaconda3\python.exe D:/pythonProject3/main.py
(200, 1, 3)
height:200 width:1 channels:3
Traceback (most recent call last):
  File "D:/pythonProject3/main.py", line 21, in <module>
    access_pixels(src1)
  File "D:/pythonProject3/main.py", line 13, in access_pixels
    pv=image[height,width,channels]
IndexError: index 200 is out of bounds for axis 0 with size 200

Process finished with exit code 1

 

即IndexError，200这个数值怎么调整都不行。

Answer 1

如果你想修改像素值为原来的与255的差, 那么13行应该改成pv = img[row, col, c]

不过提醒一下, 三个for循环速度非常慢, 而且也影响观感

广播能很好的解决这个机制, 整个函数可以写成

def access_pixels(image):
    image = 255-image
    cv.imshow('pixels_demo',image)