1. A method comprising: receiving a search query; ranking, based at least in part on the search query, a set of images to provide a set of ranked images; extracting visual features for individual images of the set of ranked images; determining, by one or more processors and based at least in part on the extracted visual features, a first degree of visual content similarity for individual images of the set of ranked images with respect to one or more other images of the set of ranked images; implementing, by the one or more processors, a selection algorithm to automatically select at least two confident image samples from the set of ranked images based at least in part on the first degrees of visual content similarity and based at least in part on ranking positions of individual images within the set of ranked images, wherein the at least two confident image samples automatically selected are not consecutively ordered within the set of ranked images; determining, by the one or more processors and based at least in part on the extracted visual features, a second degree of visual content similarity for individual images of the set of ranked images with respect to the at least two confident image samples; and reranking the set of ranked images based at least in part on the second degrees of visual content similarity.