Surface extraction

The goal here is to extract and create a 3D model of the surface of the blood vessels, using a level set method. The level sets are initialiazed using either the isosurface of a given intensity value (isosurface method) or a given intensity range (threshold method). A marching cube algorithm then extracts the surface.

1. Surface subdivision

The resulting surface can be subdivided using 3 methods:

linear

(original points are preserved and linear subdivisions are created in between),

butterfly

(original points are preserved and new points are added)

loop

(original points are displaced and new points are added).

The difference between the last two is the smoothness they tend to bend the surface to: C^1 for butterfly, C^2 for loop.

The executable we use is named meshing_surfacefromimage.

2. Supported file formats

  • input: a 3D isotropic image in MetaImage (.mha) format

  • output: a 3D model in STereoLithography (.stl) format

3. Parameters

  • --input.image.filename: (string) Input image

  • --output.path: (string) Output file

  • --config-file: (string) Configuration file

  • --force-rebuild=1 :(int) 0 to avoid computing if target file already exists, 1 to overwrite it

  • --pre-process.resize-from-reference-image.path: (string) Reference image to resize.

  • --method=threshold (string) method to use for level set initialization among: threshold or isosurface - --image-fusion.operator=max (string) method operator among : max, min, multiply, substract - --threshold.lower (double) lower bound for the threshold limit - --threshold.higher (double) higher bound for the threshold limit - --apply-connectivity.largest-region=1 (bool) 1 to keep the n largest connected regions, 0 to keep everything - --apply-connectivity.number=1 (int) Number n used above.

  • --post-process.subdivide-surface (bool) 1 to enable surface subdivision, 0 to disable it

  • --post-process.smooth-surface (bool) 1 to enable surface smoothing, 0 to disable it

  • --subdivide-surface.method=butterfly (string) Name of the surface subdivision method to use, among: linear, butterfly, loop - --subdivide-surface.subdivisions=1 (int) Number of subdivisions - --smooth-surface.method=taubin (string) Name of the surface smoothing method to use, among : taubin, laplace - --smooth-surface.iterations=30 (int) Number of iterations - --smooth-surface.taubin.passband=0.1 (double) Low-pass filter threshold for the Taubin method - --smooth-surface.laplace.relaxation=0.01 (double) Relaxation factor for the Laplace method

4. Troubleshooting

There is no known bug for this module. Please report any problem you may encounter.