The proposal discusses three axes of research: transfer learning, optimization of training data, and metric learning. Some work has been achieved in these domains prior to the start date. As the project started, we continued to work on metric learning, achieving state-of-the-art results for retrieval based on compact codes, transfer learning, and very efficient usage of out-of-domain training data.
In addition, we shifted our interest to a particular case on transfer learning, where one maps visually between domains in a completely unsupervised way. We propose both practical algorithms and methods that a grounded, as suggested in the proposal, by theoretical reasoning. In these contributions, face datasets serve as the main testbed for the various methods.
Unsupervised methods have been further applied elsewhere and specifically in medical imaging, where we also applied advanced supervised methods. The generation of images is a major task in unsupervised learning and excellent conditional image generation results were presented by the team. In addition, we have studied unsupervised learning of facial transformations and worked on lip synchronization in facial videos.
Our work on learning representations that are more robust, using the multiverse networks, continued in applications to NLP and has taken a turn into a method to condition training and theoretical analysis of deep neural networks. Our interest evolved toward the use of another form of network adaptivity called hypernetworks, with which we obtain state-of-the-art results in 3D reconstruction.
Together with the shift of the research community, following societal concerns, toward privacy, fairness, and interpretability, the topic of explainability has become a major interest of ours. Our work sheds light on the reasoning of black-box classifiers and also designs recommendation systems that are explainable. A major emphasis was put on employing explainable AI systems for better classification and image generation. Another, orthogonal, line of effort in exposing the inner workings of AI models was dedicated to describing images with text.
In the realm of securing face recognition systems by studying their vulnerabilities, we obtained a paper award at the Face and Gesture 2021 conference for a work describing a dictionary attack that is based on employing StyleGAN and then extended this work to 3D. We also worked on semantic face editing, and on representing real-world images in a latent space of StyleGAN. This last work has won the best paper award at SCIA 2023.
As recent work demonstrates, image generation is crucial for both training and attaching face recognition systems. We also explored generative algorithms for other vision problems were also for audio and other non-vision modalities.