This snippet demonstrates the use of hsv color space in editing the overall color output of the image

color_editor.py

import cv2
import numpy as np

#Reading an image (https://i.imgur.com/cdmHQiR.jpg)
img = cv2.imread('blue.jpg')
cv2.imshow('Original', img)

#Converting image to HSV Colorspace
hsv = cv2.cvtColor(img, cv2.COLOR_BGR2HSV)
cv2.imshow('HSV', hsv)

#Splitting each component into different numpy array
h = hsv[:,:,0]
s = hsv[:,:,1]
v = hsv[:,:,2]

#Empty numpy array
hsv_new = np.zeros(hsv.shape, dtype=hsv.dtype)

#Dummy function for trackbar callback
def nothing(x):
    pass

#Creating Trackbars
cv2.namedWindow('HSV_Sliders')
cv2.createTrackbar('Hue', 'HSV_Sliders', 0, 255, nothing)
cv2.createTrackbar('Sat', 'HSV_Sliders', 0, 255, nothing)
cv2.createTrackbar('Value', 'HSV_Sliders', 0, 255, nothing)

while 1:
    #Getting Trackbar position
    hue = cv2.getTrackbarPos('Hue', 'HSV_Sliders')
    sat = cv2.getTrackbarPos('Sat', 'HSV_Sliders')
    val = cv2.getTrackbarPos('Value', 'HSV_Sliders')
    
    #Changing the image color by using the trackbar position value
    hsv_new[:,:,0] = h/255*hue
    hsv_new[:,:,1] = s/255*sat
    hsv_new[:,:,2] = v/255*val
    
    #Converting back to BGR image
    hsv_new = cv2.cvtColor(hsv_new, cv2.COLOR_HSV2BGR)
    cv2.imshow('HSV_new', hsv_new)
    
    #Listening for key press events
    key = cv2.waitKey(1) & 0xFF
    #Quit if Esc key is pressed 
    if key == 27:
        break
    #Write new image to file if 's' key is pressed     
    if key == ord('s'):
        fi_name = 'h_{}_s_{}_v_{}.jpg'.format(hue, sat, val)
        cv2.imwrite(fi_name, hsv_new)