# CombinedImages.py
#
# Description: Take two images (2 files) as input
#              1) Image A is the foreground object in front of a green screen
#              2) Image B is the background
#              and combine them.
#              Once combined, the resulting image has the foreground object in
#              front of the background.
#
# Author: AL and AL
# Date: 2024

# Import necessary Python Imaging Library (PIL)
from PIL import Image

# Import our own colour module!!!
import myColourModule

# ***Main part of our program

# Create output image - result of combining images
imageOutput = Image.open("kid-green.jpg")

# Get width and height of image
width = imageOutput.width
height = imageOutput.height

# Open the file containing the foreground object with green screen -> A
# and load its content
imageKidOpen = Image.open("kid-green.jpg")
imageKidLoaded = imageKidOpen.load()

# Open the file containing the background -> B
# and load its content
imageBeachOpen = Image.open("beach.jpg")
imageBeachLoaded = imageBeachOpen.load()

# Go through each pixel of A
# First: for each row
for j in range(height):
  # Second: for each cell in each row
  for i in range(width):
    r = imageKidLoaded[i,j][0] # Red part of the RGB colour value (tuple)
    g = imageKidLoaded[i,j][1] # Green part of the RGB colour value (tuple)
    b = imageKidLoaded[i,j][2] # Blue part of the RGB colour value (tuple)

    # If it is green
    if myColourModule.isPixelGreen(r,g,b):

      # We replace it with the corresponding pixel in B
      # Get the coordinates of this pixel
      xy = (i,j)

      # Get the colour tupple (r,g,b) of the corresponding pixel in B 
      # -> image of the beach
      colour = imageBeachLoaded[i,j]

      # Change the colour of the corresponding pixel in the output image 
      # to the colour of the corresponding pixel in the beach image
      # Note: The putpixel( ) function takes two arguments. 
      # The first one is the coordinates of the pixel in the image that we 
      # want to modify, and the second argument is the colour to modify it to.
      imageOutput.putpixel(xy, colour)

# Save the resulting image
imageOutput.save("combinedImages.png", "png")

# Close the image files
imageKidOpen.close()
imageBeachOpen.close()
imageOutput.close()