Pray for Ukraine
- A practice to blend two images by using
cv2 - Generate Ukrainian flag with
numpy - Reference ☞ https://opencv-python.readthedocs.io/
# 0. Import libraries
import cv2 # install "opencv-python", but import "cv2"
import numpy as np # for using np.full()
import matplotlib.pyplot as plt# 1. Call img1
path = "Images/UkrainianPresidentZelenskyy.png" # ★ input your image ★
img1 = cv2.imread(path, cv2.IMREAD_COLOR)
# cv2.imshow("image", img1) # test : ok
# cv2.waitKey(0)
# 2. Call img2 : generate an Ukrainian flag to fit with the img1's size
h, w, c = img1.shape
# print(h, w, c) # test : ok
h2_1 = int(h/2) # h/2 without int() returns float, that occurs error in np.full()
h2_2 = h - h2_1
sapphire = (0xBB, 0x5B, 0x00) # Ukrainian flag color 1 : not RGB, but BGR
cyberYellow = (0x00, 0xD5, 0xFF) # Ukrainian flag color 2 : not RGB, but BGR
img2_1 = np.full((h2_1, w, 3), sapphire, dtype=np.uint8) # not "unit8"!
img2_2 = np.full((h2_2, w, 3), cyberYellow, dtype=np.uint8)
img2 = cv2.vconcat([img2_1, img2_2])
# cv2.imshow("image", img2) # test : ok
# cv2.waitKey(0)
cv2.imwrite("Images/UkrainianFlag.png", img2)
# 3. Blend two images and save it
alpha = 0.5
img3 = cv2.addWeighted(img1, alpha, img2, 1 - alpha, 0)
cv2.imshow("image", img3)
cv2.waitKey(0)
cv2.imwrite("Images/UkrainianFlagBlended.png", img3)
# 3.1 Show images on multiple figures
fig = plt.figure()
rows = 1; cols = 3
ax1 = fig.add_subplot(rows, cols, 1)
ax1.imshow(img1)
ax2 = fig.add_subplot(rows, cols, 2)
ax2.imshow(img2)
ax3 = fig.add_subplot(rows, cols, 3)
ax3.imshow(img3)
plt.show() # crazy colors