Granular Privacy Control for Geolocation with Vision Language Models
Authors: name: Ethan Mendes, name: Yang Chen, name: James Hays, name: Sauvik Das, name: Wei Xu, name: Alan Ritter

Vision Language Models (VLMs) are rapidly advancing in their capability to
answer information-seeking questions. As these models are widely deployed in
consumer applications, they could lead to new privacy risks due to emergent
abilities to identify people in photos, geolocate images, etc. As we
demonstrate, somewhat surprisingly, current open-source and proprietary VLMs
are very capable image geolocators, making widespread geolocation with VLMs an
immediate privacy risk, rather than merely a theoretical future concern. As a
first step to address this challenge, we develop a new benchmark, GPTGeoChat,
to test the ability of VLMs to moderate geolocation dialogues with users. We
collect a set of 1,000 image geolocation conversations between in-house
annotators and GPT-4v, which are annotated with the granularity of location
information revealed at each turn. Using this new dataset, we evaluate the
ability of various VLMs to moderate GPT-4v geolocation conversations by
determining when too much location information has been revealed. We find that
custom fine-tuned models perform on par with prompted API-based models when
identifying leaked location information at the country or city level; however,
fine-tuning on supervised data appears to be needed to accurately moderate
finer granularities, such as the name of a restaurant or building.