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Fast ray-tracing of rectilinear volume data

  • Miloš Šrámek
Part of the Eurographics book series (EUROGRAPH)

Abstract

Tomographic devices often produce data with directionally and spatially dependent resolution. Resampling to cubic voxels is possible at the cost of a significant increase of data volume and rendering time. We present an algorithm for direct ray tracing of rectilinear grids, which enables the implementation of surface rendering with subvoxel surface detection based on local interpolation, as well as different volume rendering techniques (color compositing, re-projection, maximum intensity projection). Further we present a faster version of the basic algorithm, based on cubic macro-regions assigned to each background voxel. Each macro-region is defined by its chessboard distance to the nearest foreground voxel and can be skipped during the scene traversal. The speed-up is thus gained by increasing the step along the ray, maintaining 6-connectivity of the ray in the object vicinity, which is necessary for correct surface detection.

Keywords

Single Voxel Free Zone Empty Region Volume Rendering Technique Traversal Algorithm 
These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.

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References

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Copyright information

© Springer-Verlag/Wien 1996

Authors and Affiliations

  • Miloš Šrámek
    • 1
  1. 1.Institute of Measurement ScienceSlovak Academy of SciencesBratislavaSlovak Republic

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