发表机构
Massachusetts Institute of Technology; City Form Lab（麻省理工学院; 城市形态实验室）
机构由 AI 辅助整理，请以论文原文为准。AI 中文总结
提出视觉语言框架，从街景图像提取社会指标，生成社会居住指数，应用于纽约市102,514个侧视图，发现行人流量与社会活动强度弱相关。
AI 中文摘要
虽然已有多种方法用于统计街景图像中的行人数量，但这些方法大多忽略了行人活动的社会维度。一条有大量行人穿行的街道与一条人们逗留、闲坐和社交的街道，其行人数量可能相同。本文提出了一种从街景图像中提取社会指标的视觉语言框架。全景街景图像被重新投影为面向人行道的侧视图，并保留时间戳。基于视觉语言模型（VLM）的活动检测系统对每个人在十个独立的可观察维度上进行编码，解决了模型在高层次社会类别提示下将可观察状态与上下文推断混淆的系统性失败模式。由此产生的社会指标系统生成了社会居住指数（SDI），该指数联合考虑行人群体和逗留情况，提供记录行为多样性的活动标签，并发布关于无障碍敏感人群存在的二进制标志。我们将该框架应用于纽约市的102,514个侧视图，揭示出行人流量与SDI仅呈弱相关（r = 0.168）：行人流量最高的街道并非社会活动最密集的场所。该框架提供了一种可扩展的方法，不仅测量城市人行道上有多少人，还测量他们的群体、姿态和活动类型，总结了城市人行道上发生的非短暂活动。
英文摘要
While a number of methods exist for counting pedestrians in street-view imagery, these mostly ignore the social dimensions of pedestrian activity. A street traversed by a high volume of pedestrians has the same headcount as a street where people linger, sit, and socialize. This paper presents a vision-language framework for extracting social indicators from street-level imagery. Panoramic street-level imagery is reprojected to sidewalk-facing sideviews with preserved timestamps. A vision-language model (VLM)-based activity detection system codes each person across ten independent observable dimensions, resolving a systematic failure mode in which models prompted with high-level social categories conflate observable states with contextual inferences. The resulting social indicator system produces a Social Dwelling Index (SDI) that jointly considers pedestrian grouping and dwelling, provides activity labels documenting behavioral diversity, and issues binary flags for the presence of accessibility-sensitive populations. We apply the framework to 102,514 sideviews in New York City, revealing that pedestrian volume and SDI are only weakly associated (r = 0.168): streets with the highest foot traffic are not where social activity is most intense. The framework provides a scalable method for measuring not only how many people are on city sidewalks, but also their grouping, posture, and activity type, summarizing the non-transient activities that occur on city sidewalks.
