ECCV 2026 · Malmö

GEO-Detective: Unveiling Location Privacy Risks in Images with LLM Agents

Xinyu Zhang1,2, Yixin Wu1,2, Boyang Zhang1,2, Chenhao Lin3, Chao Shen3, Michael Backes1, Yang Zhang1
1CISPA Helmholtz Center for Information Security 2Saarland University 3Xi'an Jiaotong University
The four-stage GEO-Detective workflow
GEO-Detective grades image difficulty, selects tools, gathers external evidence, synthesizes geographic clues, and iteratively refines uncertain predictions.

Abstract

Images shared on social media often expose geographic cues. While early geolocation methods required expert effort and lacked generalization, large vision-language models now make location inference accessible to ordinary users. To explore the full potential and associated privacy risks, we present GEO-Detective, an agent that mimics human reasoning and tool use for image geolocation.

The agent follows a four-stage procedure that adaptively selects strategies based on image difficulty and uses specialized tools such as visual reverse search. GEO-Detective improves over baseline LVLMs, especially on images with sparse geographic features, and reduces “unknown” predictions by more than half when external clues are available. Our defense evaluation further shows that agentic geolocation remains difficult to suppress, highlighting the need for stronger location-privacy safeguards.

Method

GEO-Detective mirrors how a human investigator changes strategy as visible clues become weaker.

01

Visual Feature Analysis

Detect landmarks, text, architecture, terrain, and other geographic signals, then estimate image difficulty.

02

Strategy Execution

Select direct LVLM analysis, experience-augmented prompting, segmentation, or visual reverse search.

03

Results Synthesis

Compare similar images and web context, then combine the evidence into country, state, and city predictions.

04

Iterative Refinement

If results remain uncertain, change the strategy, add tools, and repeat within the available resource budget.

Key Results

The largest gains appear when images contain sparse or subtle geographic evidence.

47.5%IM2GPS3K accuracy within 25 km
11.3%IM2GPS3K accuracy within 1 km
45.8% → 22.6%Unknown rate on difficult images
Interactive comparison · o3

Accuracy by image difficulty

Accuracy (%)

MP16-Pro1,000-image test set IM2GPS3K3,000 geotagged images DoxBench500 recent images LVLMso3 · GPT-4o · Gemini 2.5
From the paper

Selected quantitative results

Switch between benchmark performance and prediction uncertainty.

IM2GPS3K benchmarkGeolocation accuracy (%)
Table 2
TypeMethod@1 km@25 km
AgentGEO-Detective (Ours)11.347.5
AgentGeoMiner10.846.7
AgentsmileGeo10.938.2
LVLMG316.640.9
LVLMImg2Loc15.339.8
LVLMGeoReasoner9.933.8
TrainedPIGEON11.336.7
TrainedGeoCLIP14.134.5

Takeaway: GEO-Detective achieves the best @25 km result among the evaluated agentic LVLM frameworks. G3 remains strongest at @1 km overall.

Privacy Defenses

A visible geolocation-prohibition watermark was the only tested defense that strongly suppressed agent outputs.

84% unknown

Watermark

Explicitly tells the model that geolocation is prohibited.

17% unknown

Visual Prompt Injection

Adds misleading geographic text to the image.

18% unknown

Trigger-based

Introduces a small visual intervention signal.

23% unknown

EXIF Modification

Changes metadata but leaves visible scene clues intact.

Takeaway: location-privacy safeguards must address visible scene content and agentic evidence gathering—not only metadata.

Poster

ECCV 2026 · Malmö, Sweden

GEO-Detective ECCV 2026 poster

BibTeX

@inproceedings{zhang2026geodetective,
  title     = {GEO-Detective: Unveiling Location Privacy Risks
               in Images with LLM Agents},
  author    = {Zhang, Xinyu and Wu, Yixin and Zhang, Boyang and
               Lin, Chenhao and Shen, Chao and Backes, Michael and Zhang, Yang},
  booktitle = {European Conference on Computer Vision (ECCV)},
  year      = {2026},
  url       = {https://github.com/zxyreal/GEO-Detective}
}