DocCogito: 对齐布局认知与分步 grounded 推理以实现文档理解
DocCogito: Aligning Layout Cognition and Step-Level Grounded Reasoning for Document Understanding
AI总结:
DocCogito通过整合布局感知与结构化推理,提升文档理解的准确性和推理过程的系统性。
摘要:
文档理解需要多模态大语言模型(MLLMs)不仅提供准确答案,还需要显式的、基于证据的推理,尤其是在高风险场景中。然而,当前的文档MLLMs在形成完整的、类人推理过程方面仍存在不足,因为即使它们在布局编码和CoT式提示方面有所改进,布局与推理之间的交互通常是隐式学习的,仍然松散耦合,而非被强制作为系统机制。因此,我们提出了DocCogito,一个统一的框架,将全局布局感知与结构化、区域基础的推理相结合。DocCogito引入了一个轻量级的布局塔,将页面结构转化为可学习的全局布局先验标记,并引入了确定性的视觉-语义链(VSC)——一种比自由形式自然语言CoT更清晰的结构化表示,以监督与证据区域对齐的细粒度中间推理。训练遵循渐进式配方,包括布局感知预训练、VSC引导的冷启动、拒绝采样和GRPO。为进一步加强布局先验与VSC执行之间的内部耦合,我们增强了标准奖励,加入细粒度区域置信度信号,以鼓励推理轨迹保持与相应证据区域对齐。在六个基准(DocVQA、WTQ、ChartQA、TextVQA、OCRBench和InfoVQA)上的广泛实验表明,该方法具有强大的泛化能力,在四个基准上实现了最先进的结果。
英文摘要:
Document understanding with multimodal large language models (MLLMs) requires not only accurate answers but also explicit, evidence-grounded reasoning, especially in high-stakes scenarios. However, current document MLLMs still fall short of forming a complete, human-like reasoning process, because even when they improve both layout encoding and CoT-style prompting, the interaction between the two is typically learned implicitly and remains loosely coupled rather than being enforced as a systematic mechanism. So we propose DocCogito, a unified framework that integrates global layout perception with structured, region-grounded reasoning. DocCogito introduces a lightweight layout tower that distills page structure into learnable global layout prior tokens, and a deterministic Visual-Semantic Chain (VSC)-a concise structured representation less ambiguous than free-form natural-language CoT-to supervise fine-grained intermediate reasoning aligned with evidence regions. Training follows a progressive recipe, including layout perception pretraining, VSC-guided cold start, rejection sampling, and GRPO. To further strengthen the internal coupling between layout priors and VSC execution, we augment standard rewards with a fine-grained region-confidence signal that encourages reasoning traces to stay aligned with corresponding evidence regions. Extensive experiments on six benchmarks (DocVQA, WTQ, ChartQA, TextVQA, OCRBench, and InfoVQA) demonstrate strong generalization, achieving state-of-the-art results on four benchmarks.
机构、总结、中文摘要均由AI分析而来,可能存在错误,请以论文正文为准。