In order to protect an image search engine's users from undesirable results
adult images' classifier should be built. The information about links from
websites to images is employed to create such a classifier. These links are
represented as a bipartite website-image graph. Each vertex is equipped with
scores of adultness and decentness. The scores for image vertexes are
initialized with zero, those for website vertexes are initialized according to
a text-based website classifier. An iterative algorithm that propagates scores
within a website-image graph is described. The scores obtained are used to
classify images by choosing an appropriate threshold. The experiments on
Internet-scale data have shown that the algorithm under consideration increases
classification recall by 17% in comparison with a simple algorithm which
classifies an image as adult if it is connected with at least one adult site
(at the same precision level).Comment: 7 pages. Young Scientists Conference, 4th Russian Summer School in
Information Retrieva