Interactive Methods in Volume Visualization

Wireframe Contours

• Build a Display List of Isovalue Lines
• Wireframe Advantages:
  • Interactive Speeds
• Wireframe Disadvantages:
  • Minimal Information in Image

Multiplanar Reprojection ("slicing")

• Pseudo-color Exposed Extent and Oblique Planes
• Slicing Advantages:
  • Good for Exploring and Classifying Interactive Speeds
• Slicing Disadvantages:
  • Limited Information Viewing of Extent Planes Only

Sweeping Plane

• Volume is Transparent
• Pseudo-color Sweeping Plane(s) With Voxels at Intersection
• Sweeping Plane Advantages:
  • Good for Exploring
• Sweeping Plane Disadvantages:
  • Limited Information

A VRML World that illustrates a Sweeping Plane (from the SIGGRAPH 98 Course "Introduction to VRML 97" by Dave Nadeau, John Moreland, and Michael Heck)

Additive Reprojection

• Averages Resampled Values Behind Each Pixel
• Uses Nearest Neighbor Resampling
• I = (( å f(i,j,k) )* Bright ) / number_of_resamples
• Additive Reprojection Advantages
  • Interactive Speeds
• Additive Reprojection Disadvantages
  • Greyscale
  • No Shading

Maximum Voxel

• Maximum Resampled Value Behind Each Pixel
• Uses Nearest Neighbor Resampling
• I = Max( f(i,j,k) ) * Bright
• Maximum Voxel Advantages
  • Interactive Speeds
• Maximum Disadvantages
  • Greyscale
  • No Shading

Volume Visualization Algorithms
HyperVis Table of Contents

Last modified on February 16, 1999, G. Scott Owen, owen@siggraph.org