opencvbwimageandcolorresalted.py

opencvbwimageandcolorresalted.py

#    Copyright (c) 2022
#    Author      : Bruno Capuano
#    Create Time : 2022 Feb
#    Change Log  :
#    - Open a local image
#    - Convert an image to B&W, and resalt a specific color in RED
#
#    The MIT License (MIT)
#
#    Permission is hereby granted, free of charge, to any person obtaining a copy
#    of this software and associated documentation files (the "Software"), to deal
#    in the Software without restriction, including without limitation the rights
#    to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
#    copies of the Software, and to permit persons to whom the Software is
#    furnished to do so, subject to the following conditions:
#
#    The above copyright notice and this permission notice shall be included in
#    all copies or substantial portions of the Software.
#
#    THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
#    IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
#    FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
#    AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
#    LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
#    OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
#    THE SOFTWARE.

import numpy as np
import cv2

# open an image using opencv
imgOriginal = cv2.imread('Office2.jpg')
img = cv2.resize(imgOriginal, (324, 720))
cv2.imshow('@ElBruno - Office', img)

# get image height and width
height, width, channels = img.shape

#convert the BGR image to HSV colour space
hsv = cv2.cvtColor(img, cv2.COLOR_BGR2HSV)
#obtain the grayscale image of the original image
gray = cv2.cvtColor(img, cv2.COLOR_BGR2GRAY)

# set the bounds for the red hue
lower_red = np.array([160,100,50])
upper_red = np.array([180,255,255])

# create a mask using the bounds set
mask = cv2.inRange(hsv, lower_red, upper_red)
# create an inverse of the mask
mask_inv = cv2.bitwise_not(mask)
# Filter only the red colour from the original image using the mask(foreground)
res = cv2.bitwise_and(img, img, mask=mask)
# Filter the regions containing colours other than red from the grayscale image(background)
background = cv2.bitwise_and(gray, gray, mask = mask_inv)
# convert the one channelled grayscale background to a three channelled image
background = np.stack((background,)*3, axis=-1)
# add the foreground and the background
img_ca = cv2.add(res, background)

cv2.imshow('@ElBruno - Captain America', img_ca)

# save image using opencv
cv2.imwrite('OfficeCaptainAmerica.jpg', img_ca)

# key controller
cv2.waitKey(0)
cv2.destroyAllWindows()