全部 标题 作者
关键词 摘要

OALib Journal期刊
ISSN: 2333-9721
费用:99美元

查看量下载量

相关文章

更多...

基于结构特征的自适应光线投射算法

DOI: 10.11834/jig.20150403

Keywords: 体绘制,结构特征,自适应,光线投射

Full-Text   Cite this paper   Add to My Lib

Abstract:

目的光线投射法是一种重要的直接体绘制算法,但其效果取决于复杂的传递函数.为此提出基于结构特征的自适应光线投射算法,从而使得利用简单传递函数即可很好地揭示体数据特征.方法首先分析光线方向标量值的变化趋势获取结构特征――特征段;然后基于若干意义明确启发式规则(特征段的次序、尺度、重要度)自动计算特征段的可见度,根据特征段可见度调节每个采样点的不透明度;最后基于调节后的不透明度完成绘制.结果使用合成数据、医学真实采样数据和工业CT(computedtomography)数据进行测试,结果表明本文算法在展示体数据的内部结构特征,尤其是细小结构方面优于其他类似算法;本文算法速度比DVR(directvolumerendering)慢,但仍可满足交互需求.另外,本文算法还提供多个形象直观、意义明确的参数供用户调节,进一步增加了本文算法的灵活性.结论本文提出的自适应光线投射算法,允许用户使用简单传递函数和调节意义明显的参数即可有效揭示体数据特征,进一步提高了光线透射法的直观性.

References

[1]  Zhou F F,Fan X P,Yang B. Prospects and current studies on designing transfer function in volume rendering[J].Journal of Image and Graphics, 2008, 13(6):1034-1047 [周芳芳, 樊晓平, 杨斌. 体绘制中传递函数设计的研究现状与展望[J]. 中国图象图形学报, 2008, 13(6):1034-1047.][DOI:10.11834/jig.20080602]
[2]  Kindlmann G, Durkin J W. Semi-automatic generation of transfer functions for direct volume rendering [C]//IEEE Symposium on Volume Visualization. New York: ACM Press, 1998: 79-86.
[3]  Tzeng F Y, Lum E B, Ma K L. An intelligent system approach to higher-dimensional classification of volume data [J]. IEEE Transactions on Visualization and Computer Graphics, 2005, 11(3): 273-284.
[4]  Ruiz M, Bardera A, Boada I, et al. Automatic transfer functions based on informational divergence [J]. IEEE Transactions on Visualization and Computer Graphics, 2011, 17(12): 1932-1941.
[5]  Zhou Z G,Tao Y B,Lin H. A novel ray casting algorithm for the display of occluded features[J]. Chinese Journal of Computers, 2011, 34(3): 517-525.[周志光, 陶煜波, 林海. 一种有效揭示隐藏特征的光线投射算法[J]. 计算机学报, 2011, 34(3): 517-525.]
[6]  Bruckner S, Gr?ller M E. Instant volume visualization using maximum intensity difference accumulation [J]. Computer Graphic Forum, 2009, 28(3): 775-782.
[7]  Liang R H, Wu Y F, Dong F, et al. Accumulation of local maximum intensity for feature enhanced volume rendering [J]. The Visual Computer, 2012, 28(6-8): 625-633.
[8]  Marchesin S, Dischler J M, Mongenet C. Feature enhancement using locally adaptive volume rendering[C]//IEEE/EG International Symposium of Volume Graphics. Aire-la-Ville: Eurographics Association Press, 2007:41-48.
[9]  Marchesin S, Dischler J M, Mongenet C. Per-pixel opacity modulation for feature enhancement in volume rendering [J]. IEEE Transactions on Visualization and Computer Graphics, 2010, 16(4): 560-570.
[10]  Ma K L, Hertzmann A, Interrante V, et al. Recent advances in non-photorealistic rendering for art and visualization[J]. SIGGRAPH 2002 Course Notes, 2002: #23.
[11]  Ebert D, Rheingans P. Volume illustration: non-photorealistic rendering of volume models [J].IEEE Transactions on Visualization and Computer Graphics,2001,7(3):253-264.
[12]  Viola I, Kanitsar A, Gr?ller M E. Importance-driven feature enhancement in volume visualization [J]. IEEE Transactions on Visualization and Computer Graphics, 2005, 11(4): 408-418.
[13]  Bruckner S, Grimm S, Kanitsar A, et al. Illustrative context-preserving volume rendering[C]//Proceedings of EuroVis. Aire-la-Ville:Eurographics Association Press, 2005: 69-76.
[14]  Kraus M. Scale-invariant volume rendering [C]//Proceedings of the IEEE Visualization Conference. Los Alamitos: IEEE Computer Society Press, 2005: 295-302.
[15]  Nagy Z, Klein R. Depth-peeling for texture based volume rendering [C]//Proceedings of the 11th Pacific Conference on Computer Graphics and Applications. Washington DC:IEEE Computer Society Press, 2003: 429-433.
[16]  Borland D, Clarke J P, Fielding J R, et al. Volumetric depth peeling for medical image display [C]//Proceedings of the International Society for Optical Engineering. Bellingham WA:SPIE, 2006: 1-11.
[17]  Rezk-Salama C, Kolb A. Opacity peeling for direct volume rendering [J]. Computer Graphics Forum, 2006, 25(3): 597-606.
[18]  Liang R H, Li C, Wu F L, et al. Layered peeling algorithm of direct volume rendering for medical dataset [J]. Journal of Computer-Aided Design & Computer Graphics, 2009, 21(10): 1381-1386.[梁荣华, 李诚, 吴福理, 等. 面向医学数据的分层剥离体绘制算法[J]. 计算机辅助设计与图形学学报, 2009, 21(10): 1381-1386.]
[19]  Malik M M, M?ller T, Gr?ller M E. Feature peeling[C]//Proceedings of Graphics Interface. New York:ACM Press,2007: 273-280.
[20]  Correa C, Ma K. Visibility histograms and visibility-driven transfer functions [J]. IEEE Transactions on Visualization and Computer Graphics, 2011, 17(2): 192-204.
[21]  更多...
[22]  Wang Y H, Zhang J, Chen W, et al. Efficient opacity specification based on feature visibilities in direct volume rendering[J]. Computer Graphics Forum, 2011, 30(7): 2117-2126.

Full-Text

Contact Us

service@oalib.com

QQ:3279437679

WhatsApp +8615387084133