trackbar.py

import cv2
import numpy as np


def empty(a):
    pass


def stackImages(scale,imgArray):
    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")
cv2.resizeWindow("TrackBars", 640, 240)
cv2.createTrackbar("Hue Min", "TrackBars", 30, 179, empty)
cv2.createTrackbar("Hue Max", "TrackBars", 39, 179, empty)
cv2.createTrackbar("Sat Min", "TrackBars", 12, 255, empty)
cv2.createTrackbar("Sat Max", "TrackBars", 138, 255, empty)
cv2.createTrackbar("Val Min", "TrackBars", 164, 255, empty)
cv2.createTrackbar("Val Max", "TrackBars", 255, 255, empty)


while True:
    img = cv2.imread('resource/example2.jpg')
    imgResize = cv2.resize(img, (750, 500))
    imgHSV = cv2.cvtColor(imgResize, 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)


    kernel = np.ones((3, 3), np.uint8)
    newmask1 = cv2.erode(mask, kernel, iterations=2)
    newmask2 = cv2.dilate(newmask1, kernel, iterations=4)


    # cv2.imshow("Original", imgResize)
    # cv2.imshow("HSV", imgHSV)
    #cv2.imshow("Mask", mask)
    imgStack = stackImages(0.8, ([mask], [newmask2]))
    cv2.imshow("ImageStack", imgStack)

    cv2.waitKey(5)