Self-Supervised Learning with a Multi-Task Latent Space Objective
Pierre-François De Plaen, Abhishek Jha, Luc Van Gool, Tinne Tuytelaars, Marc Proesmans
TL;DR
The paper tackles instability in predictor-based Siamese self-supervised learning when using multi-crop augmentations. It stabilizes training by assigning a dedicated predictor to each view type while sharing the encoder, enabling effective exploitation of global and local crops; it further extends the framework with asymmetric cutout views to create a simple multi-task latent-space objective. Empirically, the approach yields consistent gains across BYOL, SimSiam, and MoCo v3 on ResNet and ViT backbones, achieving state-competitive ImageNet results and improved transfer to dense tasks like COCO. The findings highlight the primacy of spatial augmentations in SSL and open avenues for view-conditioned predictive architectures and broader modality extensions.
Abstract
Self-supervised learning (SSL) methods based on Siamese networks learn visual representations by aligning different views of the same image. The multi-crop strategy, which incorporates small local crops to global ones, enhances many SSL frameworks but causes instability in predictor-based architectures such as BYOL, SimSiam, and MoCo v3. We trace this failure to the shared predictor used across all views and demonstrate that assigning a separate predictor to each view type stabilizes multi-crop training, resulting in significant performance gains. Extending this idea, we treat each spatial transformation as a distinct alignment task and add cutout views, where part of the image is masked before encoding. This yields a simple multi-task formulation of asymmetric Siamese SSL that combines global, local, and masked views into a single framework. The approach is stable, generally applicable across backbones, and consistently improves the performance of ResNet and ViT models on ImageNet.
