Satellites Reveal Mobility: A Commuting Origin-destination Flow Generator for Global Cities

TL;DR

This paper introduces GlODGen, a satellite imagery-based generator for urban commuting origin-destination flows, enabling global city mobility analysis without traditional survey data, using vision-language models and graph diffusion techniques.

Contribution

We develop GlODGen, a novel, automated tool that leverages satellite imagery and advanced models to generate accurate OD flow data for cities worldwide, overcoming data collection challenges.

Findings

High accuracy in OD flow generation across diverse cities

Over 98% expressiveness compared to traditional data sources

Effective generalization across continents and urban environments

Abstract

Commuting Origin-destination~(OD) flows, capturing daily population mobility of citizens, are vital for sustainable development across cities around the world. However, it is challenging to obtain the data due to the high cost of travel surveys and privacy concerns. Surprisingly, we find that satellite imagery, publicly available across the globe, contains rich urban semantic signals to support high-quality OD flow generation, with over 98\% expressiveness of traditional multisource hard-to-collect urban sociodemographic, economics, land use, and point of interest data. This inspires us to design a novel data generator, GlODGen, which can generate OD flow data for any cities of interest around the world. Specifically, GlODGen first leverages Vision-Language Geo-Foundation Models to extract urban semantic signals related to human mobility from satellite imagery. These features are then combined with population data to form region-level representations, which are used to generate OD flows via graph diffusion models. Extensive experiments on 4 continents and 6 representative cities show that GlODGen has great generalizability across diverse urban environments on different continents and can generate OD flow data for global cities highly consistent with real-world mobility data. We implement GlODGen as an automated tool, seamlessly integrating data acquisition and curation, urban semantic feature extraction, and OD flow generation together. It has been released at https://github.com/tsinghua-fib-lab/generate-od-pubtools.