|
Tomographic three-dimensional reconstruction of medical image technologies of computer graphics and image science, image processing , visualization and other techniques widely used in the medical field , is currently a hot issue . Series of tomographic image reconstruction realistic three-dimensional form , to overcome the lack of two-dimensional slices diagnosis doctors can only be read by virtue of experience , help to improve the diagnostic accuracy of the doctor , has an important significance in clinical medicine and medical research . First, surface rendering technology . By tomographic image preprocessing , the body of data that can be rebuilt . Then drawn based on the contour of the surface and the MC algorithm . The emphasis is on MC algorithm , Wen pointed out that the traditional algorithm to calculate the efficiency is low , and the midpoint of the simplified method to interpolate . Unit surface and unit body topology ambiguity , the appropriate strategy to eliminate ambiguity . Due to the huge number of triangular facets of the algorithm output , it is difficult to real-time , the vertex merge to reduce the triangular facets . Finally , triangulated surfaces smooth , enhanced visual effects . Secondly, the study volume rendering techniques . The first volume rendering technology optical model . Then introduces the principles and processes of traditional ray-casting method , and analyzes the key technical data classification , color and opacity assignment , re - sampling , image synthesis . Pointed out its shortcomings, a lot of the light emitted by the number of lines , sampling points on each light , such a system of time and space overhead . In the improved algorithm , for cutting the three - dimensional data field , to reduce the sampling of the hollow body element . Using the polygon scan and starting point for the determination of reducing the sampling points on a light . The adaptive light projection and reduce the number of projected light . Finally, the study a visualization tool VTK ( Visualization Toolkit ) . First introduced VTK 's features and object model , re-use VTK to do comparison of MC algorithms and ray casting . To verify the feasibility of the improved algorithm .
|