🤖 AI Summary
Text-to-image (T2I) generation faces significant challenges in compositional synthesis—requiring precise modeling of multiple objects, diverse attributes, and intricate spatial/semantic relationships, while ensuring accurate object localization and coherent inter-object interactions. To address this, we propose CompGen, the first curriculum-based reinforcement learning framework tailored for compositional T2I generation. CompGen introduces a scene-graph–driven difficulty metric, an adaptive MCMC sampling algorithm to curate progressively challenging training data, and Group Relative Policy Optimization (GRPO) for staged policy refinement. Experiments demonstrate substantial improvements in compositional fidelity across both diffusion- and autoregressive-based T2I models, consistently outperforming random-sampling baselines. Notably, our work uncovers the first empirical scaling law linking curriculum scheduling strategies to compositional generation performance. This validates the effectiveness and generalizability of curriculum RL in T2I systems.
📝 Abstract
Text-to-Image (T2I) generation has long been an open problem, with compositional synthesis remaining particularly challenging. This task requires accurate rendering of complex scenes containing multiple objects that exhibit diverse attributes as well as intricate spatial and semantic relationships, demanding both precise object placement and coherent inter-object interactions. In this paper, we propose a novel compositional curriculum reinforcement learning framework named CompGen that addresses compositional weakness in existing T2I models. Specifically, we leverage scene graphs to establish a novel difficulty criterion for compositional ability and develop a corresponding adaptive Markov Chain Monte Carlo graph sampling algorithm. This difficulty-aware approach enables the synthesis of training curriculum data that progressively optimize T2I models through reinforcement learning. We integrate our curriculum learning approach into Group Relative Policy Optimization (GRPO) and investigate different curriculum scheduling strategies. Our experiments reveal that CompGen exhibits distinct scaling curves under different curriculum scheduling strategies, with easy-to-hard and Gaussian sampling strategies yielding superior scaling performance compared to random sampling. Extensive experiments demonstrate that CompGen significantly enhances compositional generation capabilities for both diffusion-based and auto-regressive T2I models, highlighting its effectiveness in improving the compositional T2I generation systems.