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http://dx.doi.org/10.15701/kcgs.2015.21.3.27

Ambient Occlusion Volume Rendering using Multi-Range Statistics  

Nam, Jinhyun (Dept. of Information Systems Engineering, Hansung University)
Kye, Heewon (Dept. of Information Systems Engineering, Hansung University)
Publication Information
Journal of the Korea Computer Graphics Society / v.21, no.3, 2015 , pp. 27-35 More about this Journal
Abstract
This study presents a volume rendering method using ambient occlusion which is one of global illumination methods. By considering the volume density distribution as normal distribution, ambient occlusion can be calculated at real-time speed regardless of modification of opacity transfer function. We calculate and store the averages and standard deviations of densities in a block centered at each voxel in pre-processing time. In rendering process, we determine the illumination value by estimating the nearby opacity. We generalized theoretical model and generated better quality images improving our previous research. In detail, various shapes of transfer function can be used due to the proposed equation model. Moreover, we introduced a multi-range model to give nearer objects more weight. As the result, more realistic volume rendering image can be generated at real-time speed by mixing local and ambient occlusion shading.
Keywords
Volume rendering; Medical image visualization; Global illumination; Ambient occlusion; Local statistics;
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Times Cited By KSCI : 1  (Citation Analysis)
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