# Read the PNG image using: cv2.IMREAD_UNCHANGED to retain the alpha channel.
img = cv2.imread('opencv_logo.png', cv2.IMREAD_UNCHANGED)

print(img.shape)

# Split the channels.
b, g, r, a = cv2.split(img)

# Display eazch of the channels.
plt.figure(figsize = (15,15))
plt.subplot(141); plt.imshow(b); plt.title('Blue')
plt.subplot(142); plt.imshow(g); plt.title('Green')
plt.subplot(143); plt.imshow(r); plt.title('Red')
plt.subplot(144); plt.imshow(a); plt.title('Alpha');