“…In all visual re-ranking methods, an essential problem is how to measure the visual similarity. Currently, the similarity is mainly estimated based on low-level visual features: global features [17,18,24], such as color moments and Gabor feature, and local features [8,20,22,24], such as scale invariant feature transform (SIFT) [2]. Global features work well for cases such as natural scene images, while local features do good job in rigid canonical object images.…”