Overview

This project implements Siamese Neural Networks (Siamese NN) to perform one-shot learning for facial recognition. The model compares two images and predicts their similarity, outputting 1 for identical faces and 0 for different faces. This approach is inspired by the following paper:

Koch, Gregory, Richard Zemel, and Ruslan Salakhutdinov. "Siamese neural networks for one-shot image recognition."
ICML Deep Learning Workshop. Vol. 2. No. 1. 2015.

Project Structure

• config.py: Configuration file to customize model architecture, training parameters, and data handling including augmentation. Default settings align with the best architecture from our attempts.
• dataset.py: Handles loading and preprocessing of the dataset, including pairing images based on similarity labels.
• model.py: Defines the Siamese NN architecture and includes training and prediction functions.
• main.py: Script to run visualization, training, and testing with a menu-based interface.
• mainColab.ipynb: A notebook to run experiments on Google Colab, utilizing the gratitude GPU. Also containes experiment example. Usage instructions inside.
• requirements.txt: Contains all dependencies required to run the project.
• report.pdf: A Hebrew report detailing the thought process throughout the attempts.

Base Architecture:

** Final Architecture in config.py

Dataset

The data used in this project is sourced from LFW-a Dataset, which provides aligned grayscale twin photos.

• Dataset Preparation:
  • Download and extract the dataset zip file.
  • Ensure train.txt and test.txt files are in the extracted folder, as these define how images are split into training and testing sets.
• DataLoader:
  The dataset.py module processes the folders and .txt files to create a dataset. It outputs batches like this (Menu -> 1):

Features

Building the Model

The main module offers some help in planning the CNN dimentions and needed FC dimentions based on the planned architecture (Menu -> 2).

Training

(Menu -> 3)

• Train the Siamese Neural Network from scratch using a stratified split of the dataset.
• Supports early stopping based on validation loss.
• Configurable parameters such as batch size, learning rate, and L2 regularization through config.py.

Prediction

• Load a pretrained model and evaluate its accuracy on the test set (Menu -> 4).
• Visualize sample predictions with their similarity scores.
• Visualize the worst predictions to gain insights over the model's difficulty, as well as a confidence histogram of the trained model (Menu -> 5).

Results

This problem is not very well predicted by this model, which tends to overfit. Our best attempt reached 73.9% accuracy on the test set.
We found that:

• Augmentation on the data helps, as this is a very small dataset.
• Regularization is a MUST, but with L2 and not Dropout.
• Using the original image size (250X250) with slight increase to the architecture helps.

Citations

This project utilizes the following datasets and research:

1. Gary B. Huang, Manu Ramesh, Tamara Berg, and Erik Learned-Miller.
   Labeled Faces in the Wild: A Database for Studying Face Recognition in Unconstrained Environments.
   University of Massachusetts, Amherst, Technical Report 07-49, October, 2007.

2. Lior Wolf, Tal Hassner, and Yaniv Taigman.
   Effective Face Recognition by Combining Multiple Descriptors and Learned Background Statistics.
   IEEE Transactions on Pattern Analysis and Machine Intelligence (TPAMI), 33(10), October 2011.

The aligned dataset, LFW-a, was created and contributed by Lior Wolf, Tal Hassner, and Yaniv Taigman.