annotator/binary/__init__.py

import cv2


class BinaryDetector:
    def __call__(self, img, bin_threshold):
        img_gray = cv2.cvtColor(img, cv2.COLOR_RGB2GRAY)

        if bin_threshold == 0 or bin_threshold == 255:
            # Otsu's threshold
            otsu_threshold, img_bin = cv2.threshold(img_gray, 0, 255, cv2.THRESH_BINARY_INV + cv2.THRESH_OTSU)
            print("Otsu threshold:", otsu_threshold)
        else:
            _, img_bin = cv2.threshold(img_gray, bin_threshold, 255, cv2.THRESH_BINARY_INV)

        return cv2.cvtColor(img_bin, cv2.COLOR_GRAY2RGB)