π€ AI Summary
This work addresses the limited evidence-driven reasoning capabilities of current vision-language models on super-resolution images and the absence of fine-grained evaluation protocols for their reasoning processes. To this end, the authors propose UltraVR, a diagnostic visual question answering benchmark tailored to four domains: surveillance, remote sensing, histopathology, and industrial inspection. UltraVR introduces, for the first time, a structured chain-of-thought annotation scheme comprising step-level questions, intermediate answers, and reasoning labels, enabling diagnostic analysis across the full pipelineβfrom evidence localization and local perception to final decision-making. Experimental results reveal that state-of-the-art models perform poorly in super-resolution reasoning, with errors predominantly occurring in the initial two stages; notably, downstream reasoning accuracy improves substantially when intermediate visual facts are explicitly provided.
π Abstract
Vision-language models (VLMs) excel on visual question answering and multimodal reasoning benchmarks. Yet their capability on ultra-resolution images - where critical evidence is tiny, subtle, spatially distant, or distributed - remains unclear. Existing evaluations largely report final-answer accuracy, offering limited insight into whether models acquire and integrate the necessary visual evidence. We introduce UltraVR, a diagnostic benchmark for evidence-grounded visual reasoning over ultra-resolution images. UltraVR spans four high-value scenarios: CCTV surveillance, remote sensing (RS), whole-slide image (WSI) pathology, and industrial anomaly detection (AD). These domains pose complementary challenges: fine-grained object grounding in crowded CCTV scenes, long-range spatial comparison in RS, multi-scale evidence navigation in WSI, and subtle irregularity detection in repetitive industrial layouts. Beyond standard QA triples, each instance includes a structured ground-truth chain of thought with step-level questions, intermediate answers, and reasoning labels. These labels decompose reasoning into evidence grounding, local perception, quantification, evidence integration, and decision inference, enabling process-level diagnosis over black-box scoring. Using UltraVR, we evaluate frontier VLMs and show that current models remain far from reliable on ultra-resolution reasoning. Importantly, the structured annotations allow us to localize failures across the visual-to-decision pipeline: errors concentrate in evidence grounding and local perception, while downstream inference often recovers when intermediate visual facts are supplied. These findings demonstrate UltraVR as a diagnostic testbed for measuring not only whether VLMs answer correctly, but where their ultra-resolution reasoning process breaks.