Supervised training database for building recognition by using cross ratio invariance and SVD-based method

摘要

This paper describes an approach to training a database of building images under the supervision of a user. Then it will be applied to recognize buildings in an urban scene. Given a set of training images, we first detect the building facets and calculate their properties such as area, wall color histogram and a list of local features. All facets of each building surface are used to construct a common model whose initial parameters are selected randomly from one of these facets. The common model is then updated step-by-step by spatial relationship of remaining facets and SVD-based (singular value decomposition) approximative vector. To verify the correspondence of image pairs, we proposed a new technique called cross ratio-based method which is more suitable for building surfaces than several previous approaches. Finally, the trained database is used to recognize a set of test images. The proposed method decreases the size of the database approximately 0.148 times, while automatically rejecting randomly repeated features from the scene and natural noise of local features. Furthermore, we show that the problem of multiple buildings was solved by separately analyzing each surface of a building.