By: Shengjie Lin, Yaoxuan Liu (MS Students from Columbia University)

This project is a implementation of paper Deep Koalarization: Image Colorization using CNNs and Inception-ResNet-v2 written by Federico Baldassarre, Diego González Morín, and Lucas Rodés-Guirao. Their project github page is here.

The project aims to develop a new deep learning model which combines a deep Convolutional Neural Network trained from scratch with high-level features extracted from the Inception-ResNet-v2 pre-trained model to complete image colorization tasks. Students do a comprehensive review of the paper, and then reproduce the results of it by recreating the neural network and architecture with Tensorflow and Python code. The results show that our approach is able to successfully colorize high-level image components such as the sky, the sea, the tree, the ground, and the skin. And the performance highly depends on the specific contents in the images. The comparisons between our results and the results in the original paper are fully discussed.

The model has a deep CNN architecture with Inception-ResNet-v2 pretrained on ImageNet dataset. The encoder stores the shape and edges of an image, the feature extractor extracts high level features, and finally, the decoder colorized the image. The model is trained on places dataset. All the details can be found in the report.

• To Train the model, download the dataset (500MB) from HERE, place it in the Dataset folder. Run the codes in Training section of Jupyter notebook.
• To Run the trained model and predict your picture, download the model_weights(700MB) from HERE and run the codes in Prediction section of Jupyter notebook.