Python OpenCV图像像素操作

import cv2 as cv
import numpy as np


def image_pixel(image_path: str):
    img = cv.imread(image_path, cv.IMREAD_COLOR)
    cv.imshow('input', img)

    h, w, c = img.shape
    # 遍历像素点，修改图像b,g,r值
    for row in range(h):
        for col in range(w):
            b, g, r = img[row, col]
            # img[row, col] = (255 - b, 255 - g, 255 - r)
            # img[row, col] = (255 - b, g, r)
            # img[row, col] = (255 - b, g, 255 - r)
            img[row, col] = (0, g, r)

    cv.imshow('result', img)
    cv.imwrite('images/result.jpg', img)
    cv.waitKey(0)
    cv.destroyAllWindows()

# -*-coding:utf-8-*-
"""
File Name: image_pixel_operation.py
Program IDE: PyCharm
Create File By Author: Hong
"""
import cv2 as cv
import numpy as np


def math_pixel(image_path: str):
    img = cv.imread(image_path, cv.IMREAD_COLOR)
    cv.imshow('input', img)
    h, w, c = img.shape

    blank = np.zeros_like(img)
    blank[:, :] = (2, 2, 2)  # 所有像素值设为50

    # 改变图像亮度
    mask = cv.add(img, blank)  # 图像加操作。图像形状一样就可以相加，像素值类型不一样不影响, 人为的增加了亮度
    mask = cv.subtract(img, blank)  # 图像减操作。人为的降低了亮度

    # 改变图像对比度
    # result = cv.divide(img, blank)  # 图像除操作
    result = cv.multiply(img, blank)  # 图像乘操作

    cv.imshow('blank', blank)
    cv.imshow('mask', mask)
    cv.imshow('contrast', result)
    cv.waitKey(0)
    cv.destroyAllWindows()