US Patent 7272593 Method and apparatus for similarity retrieval from iterative refinement

An iterative refinement algorithm for content-based retrieval of images based on low-level features such as textures, color histograms, and shapes that can be described by feature vectors. This technique adjusts the original feature space to the new application by performing nonlinear multidimensional scaling. Consequently, the transformed distance of those feature vectors which are considered to be similar is minimized in the new feature space. Meanwhile, the distance among clusters are maintained. User feedback is utilized to refine the query, by dynamically adjusting the similarity measure and modifying the linear transform of features, along with revising the feature vectors.