去除驾驶执照中的水印

Hi team, If I remove image background(watermark) from Driving Licence , in that case the ID was removed from that remove.How can I get ID of the Driving Licence.Could anyone please help me on this.

我尝试过的：

import cv2
import numpy as np

src = cv2.imread("D:/python_code/opencv-text-recognition/images/DL18.jpg")
gray = cv2.cvtColor(src, cv2.COLOR_BGR2GRAY)

#remove background
alpha = 3.0
beta = -200
new = alpha * gray + beta
new = np.clip(new, 0, 255).astype(np.uint8)

blur = cv2.GaussianBlur(new, (3, 3), 0)

th1 = cv2.adaptiveThreshold(blur, 255, cv2.ADAPTIVE_THRESH_MEAN_C, cv2.THRESH_BINARY, 11, 2)

#Denoising
dst = cv2.fastNlMeansDenoising(blur, None, 3, 7, 21)

cv2.imshow("OUTPUT", dst)

k = cv2.waitKey(0)
if k == 27:  # wait for ESC key to exit, ESC represented as ASCII code 27 in decimal
    cv2.destroyAllWindows()
elif k == ord('s'):  # wait for 's' key to save and exit
    cv2.imwrite("D:/python_code/opencv-text-recognition/images/OUTPUT.jpg",dst)
    cv2.destroyAllWindows()