[Fast 3D surface rendering for CT or MR image on a personal computer].

Objective. To design a 3D surface reconstruction algorithm capable of reconstructing 3D shapes of the organs, bones and tissues rapidly from CT or MR image on a personal computer. Method. By transforming and decomposing the projection of the discrete 3D data field into shear transformation and warp transformation, a Shear-Warp algorithm realizing the 3D reconstruction was established. The algorithm reduce the amount of computation obviously. The 3D surface was reconstructed by using the principle of the parallel projection, basing on the Shear-Warp algorithm. Shear transformation was performed on the volume data at first. Then the warped 3D surface was obtained by making a threshold in the sheared space. The brightness of the 3D surface was calculated using Phong brightness model, and the final image was generated through the Warp transformation. Result. A direct 3D surface reconstruction algorithm was established basing on a principle of projection from the Shear-Warp algorithm, which was able to display 3D surface on a personal computer rapidly. Conclusion. Compared with other surface reconstruction algorithms, the proposed algorithm has the advantages of no preprocessing, no intermediate data are generated in the reconstruction. With this new algorithm, it is possible to realize fast 3D surface rendering for medical images on a personal computer without the support of any hardware accelerator.