An Engineering Drawings Retrieval Method based on Density Feature and improved Moment Invariants

A novel engineering drawings feature extraction and retrieval method is proposed in this paper which comprehensively utilizes density feature and improved moment invariants. This paper defines the density feature which can reflect the spatial information of objects in the engineering drawings and presents its extraction method. Improved moment invariants can describe the shape information of the objects from the whole aspect, with translation, rotation and scale invariance. The linear weighted method of multi-feature is proposed to calculate the integrated similarity, using density feature and improved moment invariants. The retrieval results which have the higher similarity scores are returned to the user. Compared with other retrieval methods, experimental results prove that this method is effective and has the better retrieval performance.