python 修剪二值图

画一个区域，把区域值改为白色前景。

import glob

import cv2
import numpy as np

if __name__ == '__main__':

    dir_a=r'C:\big'

    files=glob.glob(dir_a+'/*_mask.jpg')

    for file in files:

        mask_img=cv2.imread(file, cv2.IMREAD_UNCHANGED)

        img_path=file.replace("_mask.jpg","_img.jpg")

        img_o=cv2.imread(img_path)

        cv2.imshow("img_o",img_o)

        while True:
            roi = cv2.selectROI(windowName="roi", img=mask_img, showCrosshair=True, fromCenter=False)
            x, y, w, h = roi

            input_box = np.array([x, y, x + w, y + h])
            print(input_box)

            mask_img[y:y+h,x:x+w]=0
            cv2.imshow("mask_img",mask_img)
            key = cv2.waitKey(1) & 0xFF
            if key == ord('c'):
                continue
            else:
                break
        cv2.imwrite(file,mask_img)