Overview of the Personal Photo Retrieval Pilot Task at ImageCLEF 2012.
David Zellhöfer · 2012
Abstract. As a consequence of a discussion at ImageCLEF 2011, the personal photo retrieval pilot task has been designed to represent a personal photo collection. In contrast to other existing collections where the contributors often remain unknown, the proposed collection has been sampled from 19 layperson photographers and enriched by their demographics. To ensure a variance in photographic motifs and style, the contributors have been chosen from different demographic groups. Thus, one can interpret the content of the collection as a mirror of a photographer’s lifespan with typical changing usage behaviors, cameras, topics, and places. The task consists of two subtasks. The first task is aiming at retrieving visual concepts such as trees, animals, or market scenes. The second is focussing on the retrieval of particular events such as parties or rock concerts. To solve both tasks, the participants were provided with queryby-example documents in addition to browsing data. The participation in this task was very low as only three groups submitted results. To summarize the first subtask, the best group achieved a precision at 20 of 0.7333 and a NDCG at 20 of 0.5459. In contrast, the second subtask focussing on events was solved with a precision at 20 of 0.9333 and a NDCG at 20 of 0.9697. Regarding the provided browsing data, only one group decided to exploit this resource instead of the provided metadata. Interestingly, it could use this data successfully to solve subtask 1 but reached the last position at subtask 2. This result indicates that there is a particularly strong influence of metadata on the retrieval of events.