filename : Kan23b.pdf entry : inproceedings conference : IEEE/CVF International Conference on Computer Vision (ICCV) Workshops, Paris, France, 2-6 October, 2023 pages : 3159-3169 year : 2023 month : 10 title : Controllable Inversion of Black-Box Face Recognition Models via Diffusion subtitle : author : Manuel Kansy, Anton Raƫl, Graziana Mignone, Jacek Naruniec, Christopher Schroers, Markus Gross, Romann M. Weber booktitle : Proceedings of the IEEE/CVF International Conference on Computer Vision (ICCV) Workshops ISSN/ISBN : 2473-9944 / 979-8-3503-0744-3 editor : publisher : IEEE publ.place : volume : issue : language : English keywords : black-box inversion, face recognition models, diffusion models, image generation, controllable face generation, analysis of neural networks abstract : Face recognition models embed a face image into a low-dimensional identity vector containing abstract encodings of identity-specific facial features that allow individuals to be distinguished from one another. We tackle the challenging task of inverting the latent space of pre-trained face recognition models without full model access (i.e. black-box setting). A variety of methods have been proposed in literature for this task, but they have serious shortcomings such as a lack of realistic outputs and strong requirements for the data set and accessibility of the face recognition model. By analyzing the black-box inversion problem, we show that the conditional diffusion model loss naturally emerges and that we can effectively sample from the inverse distribution even without an identity-specific loss. Our method, named identity denoising diffusion probabilistic model (ID3PM), leverages the stochastic nature of the denoising diffusion process to produce high-quality, identity-preserving face images with various backgrounds, lighting, poses, and expressions. We demonstrate state-of-the-art performance in terms of identity preservation and diversity both qualitatively and quantitatively, and our method is the first black-box face recognition model inversion method that offers intuitive control over the generation process.