Greenscreen-Image-Replacement

This project implements a simple greenscreen background replacement using only NumPy and Matplotlib. It loads two images — a person in front of a green screen and a forest background — as NumPy arrays, removes the green background, and combines the person with the forest image.

Features

• Green pixel detection and masking using NumPy.
• Background replacement with a new image using element-wise operations.
• Visualization of each processing step using Matplotlib.
• Saves a PNG file (person_in_forest.png) containing all stages side by side.

How to Run

• Download and extract the provided ZIP archive.
• Open a terminal in the project folder.

Install dependencies:

pip install -r requirements.txt

Run the script:

python greenscreen_replace.py

The output image person_in_forest.png will be generated in the same directory.

Output

The resulting person_in_forest.png will contain:

• The original image (with green background)
• The image after background removal

The final composite (person in forest)

Implementation Notes

Only NumPy and Matplotlib are allowed. Do not use libraries such as OpenCV or PIL.

Green pixel detection can be done using a logical mask, for example:

green_mask = (image[:, :, 1] > 100) & (image[:, :, 0] < 100) & (image[:, :, 2] < 100)

Use NumPy array indexing to combine the person and forest images.

Learning Objectives

• Understand how digital images can be represented as NumPy arrays.
• Practice element-wise array manipulation and logical masking.
• Visualize intermediate processing steps with Matplotlib.