Based on semitransparent effect

direct volume rendering method can display the small and poorly defined features of the 3D dataset.But since all voxels participate in the generation of image

rendering time is long.The quality of surface based rendering image is not very good when the segmentation is not very accurate and the topology of the suface is complex.Presented here is a algorithm which absorbs the ideas of the two above method.Firstly

we choose the opacity mapping function carefully to enhance the effect of boundary on the final image.Secondly

rendering time is reduced since only the voxels in fuzzy surface participate in the rendering process and layer is used to visualizing the human brain cortex.Results show the algorithm is good enough to rendering the complex gyrus and sulci structure of the brain cortex.