A Comparative Evaluation of Large Vision-Language Models for 2D Object Detection under SOTIF Conditions
Ji Zhou, Yilin Ding, Yongqi Zhao, Jiachen Xu, Arno Eichberger
TL;DR
The paper investigates whether Large Vision-Language Models (LVLMs) can support 2D object detection under Safety of the Intended Functionality (SOTIF) conditions by benchmarking ten LVLMs on the PeSOTIF dataset against a YOLO baseline. It introduces a unified visual-grounding pipeline with structured prompts and a JSON-based output parser to obtain bounding-box predictions without task-specific fine-tuning. The results show that top LVLMs achieve higher recall and robustness to visual degradation than the YOLO baseline in natural and adverse conditions, while conventional detectors retain higher geometric precision on crafted perturbations; latency remains a major constraint. The study underscores the potential of LVLMs as high-level safety validators in hybrid perception systems and provides a reproducible benchmark to guide future research toward lightweight distillation and improved spatial grounding for real-time deployment.
Abstract
Reliable environmental perception remains one of the main obstacles for safe operation of automated vehicles. Safety of the Intended Functionality (SOTIF) concerns safety risks from perception insufficiencies, particularly under adverse conditions where conventional detectors often falter. While Large Vision-Language Models (LVLMs) demonstrate promising semantic reasoning, their quantitative effectiveness for safety-critical 2D object detection is underexplored. This paper presents a systematic evaluation of ten representative LVLMs using the PeSOTIF dataset, a benchmark specifically curated for long-tail traffic scenarios and environmental degradations. Performance is quantitatively compared against the classical perception approach, a YOLO-based detector. Experimental results reveal a critical trade-off: top-performing LVLMs (e.g., Gemini 3, Doubao) surpass the YOLO baseline in recall by over 25% in complex natural scenarios, exhibiting superior robustness to visual degradation. Conversely, the baseline retains an advantage in geometric precision for synthetic perturbations. These findings highlight the complementary strengths of semantic reasoning versus geometric regression, supporting the use of LVLMs as high-level safety validators in SOTIF-oriented automated driving systems.
