CPlaNet: Enhancing Image Geolocalization by Combinatorial Partitioning of Maps

  • Paul Hongsuck Seo
  • Tobias Weyand
  • Jack Sim
  • Bohyung HanEmail author
Conference paper
Part of the Lecture Notes in Computer Science book series (LNCS, volume 11214)


Image geolocalization is the task of identifying the location depicted in a photo based only on its visual information. This task is inherently challenging since many photos have only few, possibly ambiguous cues to their geolocation. Recent work has cast this task as a classification problem by partitioning the earth into a set of discrete cells that correspond to geographic regions. The granularity of this partitioning presents a critical trade-off; using fewer but larger cells results in lower location accuracy while using more but smaller cells reduces the number of training examples per class and increases model size, making the model prone to overfitting. To tackle this issue, we propose a simple but effective algorithm, combinatorial partitioning, which generates a large number of fine-grained output classes by intersecting multiple coarse-grained partitionings of the earth. Each classifier votes for the fine-grained classes that overlap with their respective coarse-grained ones. This technique allows us to predict locations at a fine scale while maintaining sufficient training examples per class. Our algorithm achieves the state-of-the-art performance in location recognition on multiple benchmark datasets.


Image geolocalization Combinatorial partitioning Fine-grained classification 



The part of this work was performed while the first and last authors were with Google, Venice, CA. This research is partly supported by the IITP grant [2017-0-01778], and the Technology Innovation Program [10073166] funded by the Korea government MSIT and MOTIE, respectively.

Supplementary material

474197_1_En_33_MOESM1_ESM.pdf (229 kb)
Supplementary material 1 (pdf 229 KB)


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Copyright information

© Springer Nature Switzerland AG 2018

Authors and Affiliations

  • Paul Hongsuck Seo
    • 1
  • Tobias Weyand
    • 2
  • Jack Sim
    • 2
  • Bohyung Han
    • 3
    Email author
  1. 1.Department of CSEPOSTECHPohangKorea
  2. 2.Google ResearchLos AngelesUSA
  3. 3.Department of ECE & ASRISeoul National UniversitySeoulKorea

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