Robust User Community-Aware Landmark Photo Retrieval

Given a query photo characterizing a location-aware landmark shot by a user, landmark retrieval is about returning a set of photos ordered in their similarities to the photo. Existing studies on landmark retrieval focus on exploiting location-aware visual features or attributes to conduct a matching process between candidate images and a query image. However, these approaches are based on a hypothesis that a landmark of interest is well-captured and distinctive enough to be distinguished from others. In fact, distinctive landmarks may be biasedly taken due to bad viewpoints or angles. This will discourage the recognition results if a biased query photo is issued. In this paper, we present a novel approach towards landmark retrieval by exploiting the dimension of user community. Our approach in this system consists of three steps. First, we extract communities based on user interest which can characterize a group of users in terms of their social media activities such as user-generated contents/comments. Then, a group of photos that are recommended by the community to which the query user belongs, together with the query photo, can constitute a set of multiple queries. Finally, a pattern mining algorithm is presented to discover regular landmark-specific patterns from this multi-query set. These patterns can faithfully represent the characteristics of a landmark of interest. Experiments conducted on benchmarks are conducted to show the effectiveness of our approach.