SIGMA-GEN: Structure and Identity Guided Multi-subject Assembly for Image Generation
Abstract
We present SIGMA-GEN, a unified framework for multi-identity preserving image generation. Unlike prior approaches, SIGMA-GEN is the first to enable single-pass multi-subject identity-preserved generation guided by both structural and spatial constraints. A key strength of our method is its ability to support user guidance at various levels of precision — from coarse 2D or 3D boxes to pixel-level segmentations and depth — with a single model. To enable this, we introduce SIGMA-SET27K, a novel synthetic dataset that provides identity, structure, and spatial information for over 100k unique subjects across 27k images. Through extensive evaluation we demonstrate that SIGMA-GEN achieves state-of-the-art performance in identity preservation, image generation quality, and speed.
SIGMA-GEN can enable single and multi-subject insertion in one pass.
SIGMA-GEN can leverage different amounts of depth information.
SIGMA-GEN can be used for subject reposing.
SIGMA-GEN can handle mask shapes not seen during training.
SIGMA-GEN can handle different granularity levels of condition in single generation.
SIGMA-GEN can be used with changing styles of subjects using text.
More coming soon
BibTeX
@misc{saha2025sigmagen,
title={SIGMA-GEN: Structure and Identity Guided Multi-subject Assembly for Image Generation},
author={Oindrila Saha and Vojtech Krs and Radomir Mech and Subhransu Maji and Kevin Blackburn-Matzen and Matheus Gadelha},
year={2025},
eprint={2510.06469},
archivePrefix={arXiv},
primaryClass={cs.CV}
}