https://stackoverflow.com/questions/7624765/converting-an-opencv-image-to-black-and-white
import cv2 im_gray = cv2.imread('grayscale_image.png', cv2.CV_LOAD_IMAGE_GRAYSCALE) (thresh, im_bw) = cv2.threshold(im_gray, 128, 255, cv2.THRESH_BINARY | cv2.THRESH_OTSU) thresh = 127 im_bw = cv2.threshold(im_gray, thresh, 255, cv2.THRESH_BINARY)[1] cv2.imwrite('bw_image.png', im_bw)
