AI终于能边看边想边画了
现在的多模态AI(比如能同时处理文字和图片的模型)在生成图文混合内容时,往往把文字和图片分开训练:文字用强化学习优化,图片却用监督学习,导致模型无法从整体效果中学习。这篇研究提出BRAID框架,把多轮图文交互统一成一个决策过程,让强化学习同时优化文字和图片生成。关键创新是:用一个视觉语言模型当裁判,对每一步生成的图片打分(比如这张图对推理有没有用),从而给模型更细粒度的反馈。在空间推理和视觉感知测试中,BRAID显著优于现有方法。它不是你明天就能用的工具,但指明了多模态AI从“能看能说”进化到“会思考”的关键路径。
📄 原文摘要(英文)
Unified multi-modal models (UMMs) have shown promising interleaved text-image reasoning capabilities, yet effectively optimizing such multi-turn generation via reinforcement learning (RL) remains an open challenge. Existing approaches apply RL exclusively to text steps, relegating image generation to supervised surrogates, preventing policy gradients from propagating through the full interleaved trajectory across heterogeneous modalities. This leaves the potential of RL for UMMs largely untapped. In the paper, we introduce BRAID (Bridging inteRleAved multI-modal reasoning as a unified Decision process), a simple framework that casts multi-turn text-image-text reasoning as a unified Markov decision process (MDP), enabling joint optimization of textual and visual generation via a single, principled RL objective. BRAID computes a shared trajectory-level advantage and propagates it coherently into both text tokens and image denoising paths, each optimized through its modality-native policy gradient mechanism. To further address long-horizon credit assignment, BRAID employs a vision-language model (VLM) judge that scores each intermediate image on its reasoning utility, supplying dense turn-level feedback to sharpen learning at critical visual branches. Experiments on spatial reasoning and visual perception benchmarks show that BRAID consistently outperforms various baselines, confirming that a unified MDP formulation with vision-thinking guidance is essential for effective multi-modal reasoning.