import cv2
import numpy as np


def ex1():

    img2 = cv2.imread('/home/sense/Downloads/znak1.jpg')
    # img2 = cv2.imread('znak2.png')

    # Convert BGR to HSV
    hsv2 = cv2.cvtColor(img2, cv2.COLOR_BGR2HSV)
    # hsv2 = cv2.cvtColor(img2, cv2.COLOR_BGR2HSV)


    # define range of blue color in HSV
    lower_yellow = np.array([10, 100, 100])
    upper_yellow = np.array([60, 255, 255])

    mask = cv2.inRange(hsv2, lower_yellow, upper_yellow)

    kernel = np.ones((3, 3), np.uint8)
    erosion = cv2.erode(mask, kernel, iterations=1)
    dilation = cv2.dilate(erosion, kernel, iterations=1)

    image, contours, hierarchy = cv2.findContours(dilation, cv2.RETR_TREE, cv2.CHAIN_APPROX_SIMPLE)
    new = cv2.drawContours(img2, contours, -1, (0, 255, 0), 3)
    # Bitwise-AND mask and original image
    res = cv2.bitwise_and(img2, img2, mask=dilation)

    cv2.imshow('frame', new)
    # cv2.imshow('mask', mask)
    cv2.imshow('res', res)

    pass


ex1()
cv2.waitKey(0)