Boosting Unconstrained Face Recognition with Targeted Style Adversary
Mohammad Saeed Ebrahimi Saadabadi, Sahar Rahimi Malakshan, Seyed Rasoul Hosseini, Nasser M. Nasrabadi
TL;DR
This work tackles domain gaps in unconstrained face recognition by introducing Targeted Style Adversary (TSA), a lightweight, hidden-space augmentation that blends labeled and unlabeled feature statistics to create challenging yet plausible styles. TSA incorporates a recognizability constraint via an entropy-based measure to avoid unrecognizable augmentations and uses a gradient-driven objective to balance FR loss with recognizability, yielding efficient, scalable training without image-space generative models. Empirical results across TinyFace, IJB-B, IJB-C, IJB-S, SCFace, and cross-resolution benchmarks show consistent gains and even state-of-the-art-like performance, along with substantial speedups (~70%) and memory reductions. The approach is orthogonal to angular-margin losses, improving their effectiveness while enabling practical deployment in large-scale FR pipelines.
Abstract
While deep face recognition models have demonstrated remarkable performance, they often struggle on the inputs from domains beyond their training data. Recent attempts aim to expand the training set by relying on computationally expensive and inherently challenging image-space augmentation of image generation modules. In an orthogonal direction, we present a simple yet effective method to expand the training data by interpolating between instance-level feature statistics across labeled and unlabeled sets. Our method, dubbed Targeted Style Adversary (TSA), is motivated by two observations: (i) the input domain is reflected in feature statistics, and (ii) face recognition model performance is influenced by style information. Shifting towards an unlabeled style implicitly synthesizes challenging training instances. We devise a recognizability metric to constraint our framework to preserve the inherent identity-related information of labeled instances. The efficacy of our method is demonstrated through evaluations on unconstrained benchmarks, outperforming or being on par with its competitors while offering nearly a 70\% improvement in training speed and 40\% less memory consumption.
