from cv2 import cv2
import numpy as np


def empty(a):
    pass

def stackImages(scale,imgArray):          #a function to stake images including gray images and to scale them down or up
    rows = len(imgArray)
    cols = len(imgArray[0])
    rowsAvailable = isinstance(imgArray[0], list)
    width = imgArray[0][0].shape[1]
    height = imgArray[0][0].shape[0]
    if rowsAvailable:
        for x in range ( 0, rows):
            for y in range(0, cols):
                if imgArray[x][y].shape[:2] == imgArray[0][0].shape [:2]:
                    imgArray[x][y] = cv2.resize(imgArray[x][y], (0, 0), None, scale, scale)
                else:
                    imgArray[x][y] = cv2.resize(imgArray[x][y], (imgArray[0][0].shape[1], imgArray[0][0].shape[0]), None, scale, scale)
                if len(imgArray[x][y].shape) == 2: imgArray[x][y]= cv2.cvtColor( imgArray[x][y], cv2.COLOR_GRAY2BGR)
        imageBlank = np.zeros((height, width, 3), np.uint8)
        hor = [imageBlank]*rows
        hor_con = [imageBlank]*rows
        for x in range(0, rows):
            hor[x] = np.hstack(imgArray[x])
        ver = np.vstack(hor)
    else:
        for x in range(0, rows):
            if imgArray[x].shape[:2] == imgArray[0].shape[:2]:
                imgArray[x] = cv2.resize(imgArray[x], (0, 0), None, scale, scale)
            else:
                imgArray[x] = cv2.resize(imgArray[x], (imgArray[0].shape[1], imgArray[0].shape[0]), None,scale, scale)
            if len(imgArray[x].shape) == 2: imgArray[x] = cv2.cvtColor(imgArray[x], cv2.COLOR_GRAY2BGR)
        hor= np.hstack(imgArray)
        ver = hor
    return ver


cv2.namedWindow("TrackBars")                                     #craeting a trackbar to find optimal values of hue , sat and val
cv2.resizeWindow("TrackBars", 640,240)
cv2.createTrackbar("Hue Min", "TrackBars",0,179,empty)
cv2.createTrackbar("Hue Max", "TrackBars",179,179,empty)
cv2.createTrackbar("Sat Min", "TrackBars",0,255,empty)
cv2.createTrackbar("Sat Max", "TrackBars",255,255,empty)
cv2.createTrackbar("Val Min", "TrackBars",0,255,empty)
cv2.createTrackbar("Val Max", "TrackBars",255,255,empty)





livecap = cv2.VideoCapture(0)
livecap.set(3, 600)                      # 3 represents height here
livecap.set(4, 400)                      # 4 represents width here
livecap.set(10, 1000)                    # 10 represents brightnes           


while True:
    success, img = livecap.read()
    imgHSV = cv2.cvtColor(img, cv2.COLOR_BGR2HSV)
    h_min = cv2.getTrackbarPos("Hue Min", "TrackBars")
    h_max = cv2.getTrackbarPos("Hue Max", "TrackBars")
    s_min = cv2.getTrackbarPos("Sat Min", "TrackBars")
    s_max = cv2.getTrackbarPos("Sat Max", "TrackBars")
    v_min = cv2.getTrackbarPos("Val Min", "TrackBars")
    v_max = cv2.getTrackbarPos("Val Max", "TrackBars")
    print(h_min,h_max,s_min,s_max,v_min,v_max)
    lower = np.array([h_min,s_min,v_min])
    upper = np.array([h_max,s_max,v_max])
    mask = cv2.inRange(imgHSV,lower,upper)                             #creating a mask image
    imgResult = cv2.bitwise_and(img,img,mask=mask)                      #imposing mask on original image
    imgStack = stackImages(0.4,([img,imgHSV],[mask,imgResult]))
    
    cv2.imshow("stacked images", imgStack)
    #cv2.imshow("img", img)
    #cv2.imshow("imgHSV", imgHSV)
    #cv2.imshow("mask", mask)
    #cv2.imshow("Final result on image", imgResult)
    if cv2.waitKey(1) & 0xFF ==ord('q'):                        # press q to exit
        break
livecap.release()
cv2.destroyAllWindows()    

