I want to process different type of image to extract actual text from noisy image .I am using open cv to do this job it is working fine but the problem is I need to set different lower threshold to convert noisy image to readable text.Is it possible to set single threshold which removes noise from all images by doing some pre processing ?
Main goal : I am trying to remove that wavy horizontal line and make the character clear to read
import cv2 # Load an color image in grayscale img = cv2.imread('it_captcha3.jpg',0) ret, thresh_img = cv2.threshold(img, 180, 255, cv2.THRESH_BINARY_INV) cv2.imshow('grey image',thresh_img) cv2.imwrite("result11.jpg", thresh_img) cv2.waitKey(0) cv2.destroyAllWindows()
Processed image : threshold used -> low: 180 high ->255,
CAPTCHA : 2
PROCESSED IMAGE: threshold used -> low: 200 high ->255
captcha : 3
processed : low -> 165 high : 255