Design On Experimental Engine System And Algorithms For 3D Model Retrieval

As 3D game and 3D animation are more and more popular, 3D models are no longer strange to common computer users. Yet, the 3D model is not a recent concept for professional computer graphics engineers. With the popularization of large commercial software on 3D model design, we can design more complex 3D models and 3D scenes. And also with the popularization of 3D models on industry design and film animation, etc, how to make effective retrieval on 3D models becomes a burgeoning task. Over Internet, some 3D retrieval web systems have appeared. Some universities, institutes and companies have even built their own elementary 3D retrieval systems.The key problem of content-based retrieval is how to effectively extract the features of 3D models and how to define similarity functions based on quantitized features. So, to find a geometrical feature based on invariable similar transform is an important problem. Because the shape feature can reflect the model's real aspect, this paper only works on shape-based feature extraction algorithms and retrieval.In order to find effective feature extraction method, this paper implements a retrieval system and makes tests and analysis on a 3D model database to make deep research on methods and algorithms which already exist. This paper mainly works on 3D wavelet moment and 3D Zernike moment and brings forward 3D wavelet moment's calculation flow. Under different dimensionality, this paper makes many experiments and gets series of recall-and -precision graphs. In 3D wavelet moment calculation flow, we need to judge a point whether it is in a 3D model. This paper brings forward a method based on directed volume to solve this problem. This method is fast and takes fewer spaces and is very suitable for the model voxelization with high complexity. In designing the system, this paper brings forward an interactive method to deal with the feedback and gets good retrieval result in model database. This paper also provides an interface to let user upload the projective images of models. After 3D reconstruction, the system can retrieve and get good result.The first chapter introduces 3D models and the shape-based 3D retrieval. The second chapter makes a survey on 3D model retrieval system and algorithms on feature extraction. The third chapter introduces the system and makes detail presentation on how to deal with the feedback. The fourth chapter introduces the method on how to judge whether a voxel is in 3D model and the interface of algorithms. The fifth chapter sums up the author's work and puts...