Python TrackBar convert the image to B&W

Question

I want to make a TrackBar that translates the image into black and white. The application is on dextop, the image is read from a file. The location of the TrackBar is at the top, above image. Advance thanks.

import os
import cv2
import numpy
import skimage
import skimage.io as io
from tkinter import *
from PIL import ImageTk

# creating canvas and settings of color and brush's  size
canvas_width = 960
canvas_height = 1280
brush_size = 3
color = 'black'


# painting
def paint(event):
    global brush_size
    global color
    x1 = event.x - brush_size
    x2 = event.x + brush_size
    y1 = event.y - brush_size
    y2 = event.y + brush_size
    w.create_oval(x1,y1,x2,y2,fill=color,outline=color)

#razmer
def brush_size_change(new_size):
    global brush_size
    brush_size = new_size
#color change
def color_change(new_color):
    global color
    color = new_color

#reading image
root = Tk()
image = ImageTk.PhotoImage(file = "C:/Users/nikit/Desktop/Практика/lb3.jpg")

#creating
w = Canvas(root,width=canvas_width,
           height=canvas_height,
           bg='white')
#bind lkm
w.bind('<B1-Motion>', paint)
#creating buttons
red_btn = Button(text='Красный',width=10,
                 command=lambda: color_change('red'))

five_btn = Button(text='5',width=5,
                  command=lambda: brush_size_change(5))

#paste image
w.create_image(1, 1, image = image, anchor = NW)

w.grid(row=2,column=0,columnspan=7,
       padx=5,pady=5,sticky=E+W+S+N)
w.columnconfigure(6, weight=1)
w.rowconfigure(2,weight=1)

#paste buttons
red_btn.grid(row=0,column=2)
five_btn.grid(row=1,column=2)



#otobrajenie
root.mainloop()

#io.imshow(img)
#io.show()

So far, there is such a code, without a trackbar. According to the comments, I think it will be clear that this code makes it possible to draw, choose the color and size of the brush. There is a problem when I try to create a TrackBar, namely: I create it through the cv2.createTrackBar command, but for some reason it does not work

Answer 1

Convert your image to HSV/HSL colourspace, and use the slider to progressively reduce saturation. When you get to zero, the image will be greyscale.

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