opencv hsv mask/filter with trackbar

track_hsvmask.py

import numpy as np
import cv2
import argparse

parser =argparse.ArgumentParser()
parser.add_argument('input_img', help = 'the input image file')
args = parser.parse_args()

def nothing(x):
    pass

def colormask(filename):
    cv2.namedWindow(filename,1)

    #set trackbar
    hh = 'hue high'
    hl = 'hue low'
    sh = 'saturation high'
    sl = 'saturation low'
    vh = 'value high'
    vl = 'value low'
    mode = 'mode'

    #set ranges
    cv2.createTrackbar(hh, filename, 0,179, nothing)
    cv2.createTrackbar(hl, filename, 0,179, nothing)
    cv2.createTrackbar(sh, filename, 0,255, nothing)
    cv2.createTrackbar(sl, filename, 0,255, nothing)
    cv2.createTrackbar(vh, filename, 0,255, nothing)
    cv2.createTrackbar(vl, filename, 0,255, nothing)
    cv2.createTrackbar(mode, filename, 0,3, nothing)

    thv= 'th1'
    cv2.createTrackbar(thv, filename, 127,255, nothing)

    #read img in both rgb and grayscale
    img = cv2.imread(filename,1)
    imgg = cv2.imread(filename,0)

    #convert rgb to hsv
    hsv_img = cv2.cvtColor(img, cv2.COLOR_BGR2HSV)

    while True:
        hul= cv2.getTrackbarPos(hl,filename)
        huh= cv2.getTrackbarPos(hh,filename)
        sal= cv2.getTrackbarPos(sl,filename)
        sah= cv2.getTrackbarPos(sh,filename)
        val= cv2.getTrackbarPos(vl,filename)
        vah= cv2.getTrackbarPos(vh,filename)
        thva= cv2.getTrackbarPos(thv,filename)

        modev= cv2.getTrackbarPos(mode,filename)

        hsvl = np.array([hul, sal, val], np.uint8)
        hsvh = np.array([huh, sah, vah], np.uint8)

        mask = cv2.inRange(hsv_img, hsvl, hsvh)

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

        #set image for differnt modes
        ret, threshold = cv2.threshold(mask, 0, 255, cv2.THRESH_BINARY_INV+cv2.THRESH_OTSU)
        ret, img_th= cv2.threshold(imgg, thva, 255, cv2.THRESH_TOZERO)
        res2 = cv2.bitwise_and(img_th, img_th, mask=threshold)
        res_rgb = cv2.cvtColor(res, cv2.COLOR_HSV2BGR)
        #convert black to white
        res[np.where((res==[0,0,0]).all(axis=2))] = [255,255,255]

        if modev ==0:
            #show mask only
            cv2.imshow(filename,mask)
        elif modev ==1:
            #show white-masked color img
            cv2.imshow(filename,res)
        elif modev ==2:
            #show white-masked binary img with threshold
            cv2.imshow(filename,threshold)
        else:
            #white-masked grayscale img with threshold
            cv2.imshow(filename,res2)

        #press 'Esc' to close the window
        ch = cv2.waitKey(5)
        if ch== 27:
            break
    cv2.destroyAllWindows()

    return mask

colormask(args.input_img)