object_detection_opencv_hsv.py

import cv2
import numpy as np

def nothing(x):
    print(x)


# Video capture
cap = cv2.VideoCapture(0) 

cv2.namedWindow('Tracking')
cv2.createTrackbar('LH' , 'Tracking',0,255,nothing) # hue - difference colors
cv2.createTrackbar('LS' , 'Tracking',0,255,nothing) # saturation - color brightness
cv2.createTrackbar('LV' , 'Tracking',0,255,nothing) # value - color intensity
cv2.createTrackbar('UH' , 'Tracking',255,255,nothing)
cv2.createTrackbar('US' , 'Tracking',255,255,nothing)
cv2.createTrackbar('UV' , 'Tracking',255,255,nothing)


while True:
    # frame = cv2.imread('test_images/smarties.png') #### For Image

    _ , frame = cap.read()

    # cv2.imshow("frame" , frame)

    hsv = cv2.cvtColor(frame , cv2.COLOR_BGR2HSV)

    l_h = cv2.getTrackbarPos('LH','Tracking')
    l_s = cv2.getTrackbarPos('LS','Tracking')
    l_v = cv2.getTrackbarPos('LV','Tracking')
    u_h = cv2.getTrackbarPos('UH','Tracking')
    u_s = cv2.getTrackbarPos('US','Tracking')
    u_v = cv2.getTrackbarPos('UV','Tracking')

    l_b = np.array([l_h,l_s,l_v,])
    u_b = np.array([u_h,u_s,u_v])
    
    mask = cv2.inRange(hsv , l_b , u_b)

    res = cv2.bitwise_and(frame , frame , mask=mask)

    # for blue ball detection 
    # l_b = [85,21,224]
    # u_b = [139,255,255]

    cv2.imshow('mask' , mask)
    cv2.imshow('res' , res)

    key = cv2.waitKey(1)
    if key == 27:
        break

cap.release()
cv2.destroyAllWindows()