Writing Green Screen
----------------------
img = new SimpleImage("yosemite.jpg");
back = new SimpleImage("paris.jpg");
back.setSameSize(image);
img.setZoom(0.5);

for (pixel : img) {
  backPixel = back.getPixel(pixel.getX(),
                          pixel.getY());
  if (pixel.isSimilarTo(63, 121, 248, 70)) {
    pixel.setRGB(backPixel.getRed(),
                 backPixel.getGreen(),
                 backPixel.getBlue());
  }
}

print(img);


Faded Green Screen
------------------
image = new SimpleImage("banana.jpg");
image.setZoom(0.5);
print(image);
back = new SimpleImage("paris.jpg");
back.setSameSize(image);
back.setZoom(0.5);

for (pixel : image) {
  backPixel = back.getPixel(pixel.getX(),
	                        pixel.getY());
  if (pixel.isSimilarTo(100, 150, 150, 70)) {
    pixel.setRGB(backPixel.getRed(),
                 backPixel.getGreen(),
                 backPixel.getBlue());
  } else {
    pixel.setRGB((pixel.getRed() + backPixel.getRed()) / 2, (pixel.getGreen() + backPixel.getGreen()) / 2, (pixel.getBlue() + backPixel.getBlue()) / 2);
  }
}

print(image);


Green Screen Multiple Passes
----------------------------
image = new SimpleImage("stop.jpg");
image.setZoom(0.5);
back1 = new SimpleImage("yosemite.jpg");
back1.setSameSize(image);
back2 = new SimpleImage("leaves.jpg");
back2.setSameSize(image);

for (pixel : image) {
  if (pixel.isSimilarTo(200, 75, 50, 70)) {
    backPixel = back2.getPixel(pixel.getX(), pixel.getY());
    pixel.setRGB(backPixel.getRed(), backPixel.getGreen(), backPixel.getBlue());
  } else {
  
  if (pixel.isSimilarTo(100, 100, 200, 70)) {
    backPixel = back1.getPixel(pixel.getX(), pixel.getY());
    pixel.setRGB(backPixel.getRed(), backPixel.getGreen(), backPixel.getBlue());
  }
  
  }
}

print(image);