Content Based3-D Model Retrieval And System Design

With the rapid development of computer hardware and software technologies and theInternet technologies, the media types used in their daily life and work time have transferredfrom simple text to text, image, audio and video. And the trend from two-dimensional tothree-dimensional becomes more and more evident. Especially in virtual reality, simulation andvirtual manufacturing and other related fields, three-dimensional model has been widely used,and there are so many three-dimensional model libraries created. However, due to the lack of aneffective retrieval tool, the existing three-dimensional models can be made full use. Therefore,the research of how to extract the features of three-dimensional models and content based3Dmodel retrieval is of great significance in the respect of theory and engineering.In this paper, based on the analysis of content based3D model retrieval related works athome and abroad, we mainly finished the following work:Firstly, we improved the algorithm of3D model retrieval based on slices. Though theexisting slice based3D model retrieval algorithm can achieved good results, its process is toocomplicated and exhausted in computing. In order to improve the efficiency of3D moderetrieval system, we redesigned the algorithm by replacing the original complex process withsimple relative area calculation that is easy computing and has same effect. Based on this, wepropose a slice based area ratio3D model retrieval algorithm. Experimental results show that theimproved significantly.Secondly, we proposed a mapping feature based3D model retrieval algorithm using3Dwavelet analysis. The algorithm first mapping the three-dimensional model’s contour and shapeattributes to a3D matrix, then decompose the3D matrix with3D wavelet and the low-frequencycomponent of the decomposed result is used for3D model retrieval. Although the algorithm stillremains deficiencies, but the results of the experiments show that the algorithm is promising.Third, we designed and implemented a3D model retrieval system based on ouralgorithms. In order to verify the feasibility and correctness of our algorithms we implementedslice-area ratio based and mapping feature based3D wavelet-based3D model retrievalsystem. The former system is based on MFC and the three-part libraries like OpenCV and OpenGL; the latter system is based on Matlab, and we used the matlab’s powerful wavelettoolbox. The basic features of a typical3D model retrieval system are implemented on oursystem such like: user input, model demonstration, model index, retrieve, attribute view and theresults demonstration.Finally, the pros and cons of our research are summarized, and the outlook of content based3D model retrieval is given based on our study.