  We present Neural Congealing -- a zero-shot self-supervised framework for
detecting and jointly aligning semantically-common content across a given set
of images. Our approach harnesses the power of pre-trained DINO-ViT features to
learn: (i) a joint semantic atlas -- a 2D grid that captures the mode of
DINO-ViT features in the input set, and (ii) dense mappings from the unified
atlas to each of the input images. We derive a new robust self-supervised
framework that optimizes the atlas representation and mappings per image set,
requiring only a few real-world images as input without any additional input
information (e.g., segmentation masks). Notably, we design our losses and
training paradigm to account only for the shared content under severe
variations in appearance, pose, background clutter or other distracting
objects. We demonstrate results on a plethora of challenging image sets
including sets of mixed domains (e.g., aligning images depicting sculpture and
artwork of cats), sets depicting related yet different object categories (e.g.,
dogs and tigers), or domains for which large-scale training data is scarce
(e.g., coffee mugs). We thoroughly evaluate our method and show that our
test-time optimization approach performs favorably compared to a
state-of-the-art method that requires extensive training on large-scale
datasets.
