Visible Woman Visualization

Project 2, CS 526
March, 2004

Ratko Jagodic

Written entirely in C++ using FLTK/FLUID for GUI. No threads, all the GUI events and display
updates are handled manually for each control.

Source files: Visible Woman (source).zip (includes VS.NET solution, source code, FLTK/FLUID files)

Binaries: Visible Woman (bin).zip

How to run:
The executable can be run on any Windows machine that has VTK installed and appropriate paths
setup (environment variables) for the libraries and dlls. Since marching cubes algorithm is being
used for extracting isosurfaces, patented .dll, .lib and .h also need to be present.
Here are the three files compiled for WinXP & VTK 4.2:
vtkPatented.dll - vtkPatented.lib - vtkMarchingCubes.h
Also, when running the executable make sure that "Female.raw" data file and "skin2.gif" image
file are in the same directory as the executable.

Features:

• Volume Rendering (raycasting):
  • fully adjustable Volume Of Interest
  • adjustable skin opacity (bone always opaque)
  • 4 different subsampling resolutions
  • MIP & Composite raycasting methods
  • linear & nearest interpolation methods
  • shading
  • adjustable sampling distance
• Isosurfaces
  • fully adjustable Volume Of Interest
  • 2 isosurfaces
  • adjustable skin opacity (bone is always opaque)
  • 4 different subsampling resolutions
  • visualization presets (optimal, speed, quality, memory and user)
  • adjustable decimation
  • image smoothing (on/off)
  • Gaussian smoothing (on/off)
  • normals (on/off)
  • memory usage reduction (on/off)
• GUI supporting all the features mentioned above
• automatic update of all the visualization paramteres
• interactive controls (zooming, rotating, panning)

Features not behaving correctly:

• when in raycasting mode and when changing VOI, the image might not always
  show up in the center of the screen. This happens because of the change in the
  center of the bounding box
• when in raycasting mode, depending on the location of the camera, the rotation
  might seem like a revolution (orbit) instead of rotation around itself. This happens
  because of the change in the "origin" of the current VOI
• when in raycasting mode, sometimes when moving from a lower resolution vis
  to a higer resolution vis, the data might get clipped. I had this happen only when
  going to a full resolution image (happened during presentation as well). However,
  I tried the same thing again when I was creating the screenshots and it worked fine
  (look at the screenshot below). Go figure...
  

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Screenshots:

Figure 1. Optimal visualization parameters (balance between speed and quality). This is the image
you get upon starting the application.

Figure 2. Quality visualization parameters (no decimation, normals On, 256*256). Notice no smoothing
in order to get the best representative image.

Figure 3. Speed optimized visualization. More decimation, no normals, smoothing, smaller resolution.
Notice the degradation in quality from the figures above.

Figure 4. Head isosurface visualization, Gaussian smoothing. VOI selected via widget shown below.

Figure 5. Greater VOI, skin totally transparent, Gaussian smooting.

Figure 6. We are not limited to just head or feet. Random VOI with totally opaque skin.

Figure 7. Raycasting. Composite with shading. Very low resolution (32*32) but smaller sampling
distance, hence higher quality image. Skin totally opaque.

Figure 8. Raycasting. Higer resolution than the previous one but greater sampling distance, hence
the skin looks like stripes instead of connected.

Figure 9. Raycasting. Composite but no shading. Notice how it's hard to perceive depth when there
is no shading even though it's rendered at the highest resolution. Also, here is one of the examples
where I went from smaller resolution to higher resolution and the image is still looking good (unlike
during the presentation).

Figure 10. Raycasting. Still composite function with shading but with "nearest interpolation" technique.
Even with the smaller sampling distance and highest resolution the image doesn't look "clean".

Figure 11. Raycasting. Different VOI (head) with lower resolution and no shading.

Figure 12. Raycasting. This time with MIP raycasting function. Since there is no shading with MIP,
it's hard to perceive depth even with lower sampling rate and higher resolution. Skin transparent.

Figure 13. Raycasting. Back to composition function but with nearest interpolation technique. The
decrease in image quality can be seen, again, making linear interpolation better.