From Broad Exploration to Stable Synthesis: Entropy-Guided Optimization for Autoregressive Image Generation
- URL: http://arxiv.org/abs/2604.02355v1
- Date: Thu, 12 Mar 2026 12:49:26 GMT
- Title: From Broad Exploration to Stable Synthesis: Entropy-Guided Optimization for Autoregressive Image Generation
- Abstract summary: Chain-of-Thought (CoT) with Reinforcement Learning (RL) improves text-to-image (T2I) generation.<n>We present a systematic entropy-based analysis that yields three key insights.<n>We propose Entropy-Guided Group Relative Policy Optimization (EG-GRPO), a fine-tuning strategy that reallocates optimization budget by uncertainty.
- Score: 53.759125791348396
- License: http://arxiv.org/licenses/nonexclusive-distrib/1.0/
- Abstract: Combining Chain-of-Thought (CoT) with Reinforcement Learning (RL) improves text-to-image (T2I) generation, yet the underlying interaction between CoT's exploration and RL's optimization remains unclear. We present a systematic entropy-based analysis that yields three key insights: (1) CoT expands the generative exploration space, while RL contracts it toward high-reward regions; (2) final reward is strongly negatively correlated with both the mean and variance of image-token entropy, highlighting the need to reduce uncertainty and instability; and (3) the entropy of the textual CoT directly governs downstream image quality, with lower-entropy CoTs leading to better generations. Motivated by these findings, we propose Entropy-Guided Group Relative Policy Optimization (EG-GRPO), a fine-tuning strategy that reallocates optimization budget by uncertainty: low-entropy tokens are excluded from reward-driven updates to preserve stability, while high-entropy tokens receive an entropy bonus that encourages structured exploration without collapse. Experiments on standard T2I benchmarks demonstrate that EG-GRPO achieves state-of-the-art performance.
Related papers
- Group Entropy-Controlled Policy Optimization [38.44352203898131]
Group Entropy-Controlled Policy Optimization (GEPO) is a lightweight extension to GRPO that uses group entropy to perform entropy-conditioned asymmetric advantage shaping.<n>GEPO attenuates positive advantages in low-entropy groups to reduce over-exploitation, and negative advantages in high-entropy groups to preserve exploration.
arXiv Detail & Related papers (2026-07-18T15:13:33Z) - Beyond Entropy: Learning from Token-Level Distributional Deviations for LLM Reasoning [36.34371525731833]
We introduce the Independent Combinatorial Tokens (ICT) framework, which shifts the optimization focus from scalar uncertainty to the distributional properties of token logits.<n>Our theoretical analysis, grounded in both Shannon and second-order Rényi entropy, proves that selectively updating on these tokens regulates policy concentration.<n> Empirical results demonstrate that updating only the top 10% of unique tokens on Qwen2.5 (0.5B/1.5B/7B) models yields an average pass@4 improvement of 4.58%, with a maximum gain of 14.9%, over GRPO, 20-Entropy, and STAPO baselines.
arXiv Detail & Related papers (2026-06-18T04:11:56Z) - STARE: Surprisal-Guided Token-Level Advantage Reweighting for Policy Entropy Stability [78.63876433996107]
We conduct a first-order gradient analysis of token-level entropy dynamics under GRPO.<n>We propose STARE, which identifies entropy-critical token subsets via batch-internal surprisal quantiles.<n>On AIME24 and AIME25, STARE outperforms DAPO and other competitive baselines by 4%-8% in average accuracy.
arXiv Detail & Related papers (2026-06-17T16:13:42Z) - Entropy Polarity in Reinforcement Fine-Tuning: Direction, Asymmetry, and Control [77.8471519867791]
Empirically, we show that entropy polarity reliably predicts entropy changes.<n>We propose Polarity-Aware Policy Optimization (PAPO), which preserves both polarity branches and implements entropy control through advantage reweighting.
arXiv Detail & Related papers (2026-05-12T08:47:05Z) - Anchoring Values in Temporal and Group Dimensions for Flow Matching Model Alignment [61.80228667422234]
VGPO redefines value estimation across both temporal and group dimensions.<n>It transforms the sparse terminal reward into dense, process-aware value estimates.<n>It replaces standard group normalization with a novel process enhanced by absolute values to maintain a stable optimization signal.
arXiv Detail & Related papers (2025-12-13T16:31:26Z) - Beyond High-Entropy Exploration: Correctness-Aware Low-Entropy Segment-Based Advantage Shaping for Reasoning LLMs [6.948242693954442]
Reinforcement Learning with Verifiable Rewards (RLVR) has become a central approach for improving the reasoning ability of large language models.<n>We propose LESS, a correctness-aware reinforcement framework that performs fine-grained advantage modulation over low-entropy segments.
arXiv Detail & Related papers (2025-11-30T14:19:36Z) - Mind Your Entropy: From Maximum Entropy to Trajectory Entropy-Constrained RL [56.085103402298905]
We propose a trajectory entropy-constrained reinforcement learning (TECRL) framework to address these two challenges.<n>Within this framework, we first separately learn two Q-functions, one associated with reward and the other with entropy, ensuring clean and stable value targets unaffected by temperature updates.<n>We develop a practical off-policy algorithm, DSAC-E, by extending the state-of-the-art distributional soft actor-critic with three refinements.
arXiv Detail & Related papers (2025-10-25T09:17:47Z) - Arbitrary Entropy Policy Optimization: Entropy Is Controllable in Reinforcement Fine-tuning [36.00460460149206]
We propose Arbitrary Entropy Policy Optimization (AEPO), which eliminates entropy collapse by replacing entropy bonuses with REINFORCE policy gradient on temperature-adjusted distributions.<n>AEPO integrates three key designs: policy gradient as regularization, distribution as regularization, and REINFORCE as regularization, enabling precise entropy control without distorting optimization.
arXiv Detail & Related papers (2025-10-09T12:24:08Z) - Delving into RL for Image Generation with CoT: A Study on DPO vs. GRPO [68.44918104224818]
Autoregressive image generation presents unique challenges distinct from Chain-of-Thought (CoT) reasoning.<n>This study provides the first comprehensive investigation of the GRPO and DPO algorithms in autoregressive image generation.<n>Our findings reveal that GRPO and DPO exhibit distinct advantages, and crucially, that reward models possessing stronger intrinsic generalization capabilities potentially enhance the generalization potential of the applied RL algorithms.
arXiv Detail & Related papers (2025-05-22T17:59:49Z) - T2I-R1: Reinforcing Image Generation with Collaborative Semantic-level and Token-level CoT [73.10972809774039]
We present T2I-R1, a novel reasoning-enhanced text-to-image generation model powered by reinforcement learning.<n>By applying our reasoning strategies to the baseline model, Janus-Pro, we achieve superior performance with 13% improvement on T2I-CompBench and 19% improvement on the WISE benchmark.
arXiv Detail & Related papers (2025-05-01T17:59:46Z)
This list is automatically generated from the titles and abstracts of the papers in this site.
This site does not guarantee the quality of this site (including all information) and is not responsible for any consequences.