Python实现简单去水印：鼠标选取区域并填充白色

import cv2 # 导入相关库
from PIL import Image

global img
global point1, point2


def on_mouse(event, x, y, flags, param):
global img, point1, point2
img2 = img.copy()
if event == cv2.EVENT_LBUTTONDOWN: # 左键点击
point1 = (x, y)
cv2.circle(img2, point1, 10, (255, 255, 255), 2)
cv2.imshow('image', img2)
elif event == cv2.EVENT_MOUSEMOVE and (flags & cv2.EVENT_FLAG_LBUTTON): # 按住左键拖曳
cv2.rectangle(img2, point1, (x, y), (255, 255, 255), 2)
cv2.imshow('image', img2)
elif event == cv2.EVENT_LBUTTONUP: # 左键释放
point2 = (x, y)
cv2.rectangle(img2, point1, point2, (255, 255, 255), 2)
cv2.imshow('image', img2)
min_x = min(point1[0], point2[0])
min_y = min(point1[1], point2[1])
width = abs(point1[0] - point2[0])
height = abs(point1[1] - point2[1])
cut_img = img[min_y:min_y + height, min_x:min_x + width]
cv2.imwrite('first.png',cut_img)

def test2():
i = 1
j = 1
img = Image.open("first.png") # 读取系统的内照片
print(img.size) # 打印图片大小
print(img.getpixel((4, 4)))
width = img.size[0] # 长度
height = img.size[1] # 宽度
for i in range(0, width): # 遍历所有长度的点
for j in range(0, height): # 遍历所有宽度的点
data = (img.getpixel((i, j))) # 打印该图片的所有点
print(data) # 打印每个像素点的颜色RGBA的值(r,g,b,alpha)
print(data[0]) # 打印RGBA的r值
if (data[0] != 255 and data[1] != 255 and data[2] != 255): # RGBA的r值大于170，并且g值大于170,并且b值大于170
img.putpixel((i, j), (255, 255, 255, 255)) # 则这些像素点的颜色改成大红色
img = img.convert("RGB") # 把图片强制转成RGB
img.save("mid.png")

def testMain():
img = Image.open('/home/gtwang/1000000.png')
img2 = Image.open('mid.png')

layer = Image.new('RGBA', img.size, (255, 255, 255, 0))
layer.paste(img2, (point1))

img_after = Image.composite(layer, img, layer)
img_after.show()
img_after.save('output.png')

def main():
global img
img = cv2.imread('input.png')
cv2.namedWindow('image')
cv2.setMouseCallback('image', on_mouse)
cv2.imshow('image', img)
cv2.waitKey(0)


if __name__ == '__main__':
main()
test2()
testMain()