Extraction Of Boundary From Relic Three-dimensional Model

Extraction of Boundary is an important part in three-dimensional model. It's extensive used in many fields, such as reassembling fractured objects, reverse engineering and model painting. This paper studies in extract the boundary of historical relics which possess the crude surface and not regular. It mainly includes following:1) Improve a boundary extraction algorithm based on integral invariants. The new algorithm used the method like the voxelization. It decrease the workload in calculate. The probable inaccuracy is also analyses in the paper and proves the inaccuracy is in the tolerance interval.2) Propose a new method of extraction of boundary based on cut section. This method aim at solve the problem of extraction the smooth boundary. The principal component analyses used to revision the direction of the model, and cut sections to differential coefficient the model to planar curve. Extracted the feature point from the curve and mapped the point to the model. At last get the boundary of the model.3) Analysis the two arithmetics by multi scale behavior, use multi scale to improve the impression of boundary extraction.4) Fitting curve of the boundary. Design two different methods for the two algorithms.5) Extraction of boundary system is designed. The system prove the research and convenient the follow-up study. Use the system extracts the boundary of terra-cotta warriors' three-demensional model and the results are well.