Anisotropic Filtering of Non-Linear Surface Features


Klaus Hildebrandt and Konrad Polthier

Zuse Institute Berlin
Geometry and Visualization

 

 

 

This page contains animations that show some experiments performed with our two anisotropic denoising algorithms, namely the anisotropic smoothing (based on the anisotropic mean curvature flow) and the prescribed smoothing (based on the prescribed mean curvature flow).

The images of each animation are consecutive snapshots. There was no post-processing neither of the images nor of the animations.

All images have been produced with JavaView.

 

 

Prescribed smoothing of the dragon
The prescribed mean curvature flow is used to filter the dragon corrupted by noise. The features of the surface are preserved while the noise is removed.

Start Animation: dragon

Anisotropic filtering of non-linear surface features 
A surface with non-linear features and feature lines with varying curvature is denoised with the prescribed mean curvature flow. The features are correctly preserved during the smoothing process.

Start animation: colored, flat shaded

Denoising of a surface with a vanishing ridge
The fandisk is a standard model of a surface with curved sharp edges and a vanishing ridge. The prescribed smoothing correctly preserves the features while the anisotropic smoothing flattens the ridge.

Start animation: prescribed MCF, anisotropic MCF

Anisotropic smoothing of the Venus head
Application of anisotropic mean curvature flow to a high resolution model corrupted by noise. Details of the surface are preserved while the noise is removed. 

Start animation: Venus

Prescribed smoothing of the bone
The prescribed mean curvature flow is used to the smooth the surface of a bone corrupted by noise. The features of the surface are preserved while the noise is removed.

Start Animation: bone
Prescribed smoothing of the dragon
The prescribed mean curvature flow is used to the filter the surface of the armadillo corrupted by noise. The features of the surface are preserved while the noise is removed.

Start Animation: armadillo

Comparison of the anisotropic and the prescribed smoothing
The ring is heavily deformed by the anisotropic flow, because the curved parts shrink while the flat parts do not move at all. Whereas the prescribed smoothing performs excellent on this surface, the ring is a stable limit surface of this flow.
Start Animation: prescribed MCF, anisotropic MCF

Denoising linear features
The octahedron is the standard model for anisotropic smoothing algorithms. The images are made to allow a comparison to results by others. Especially the comparison shows the high quality of our results.

Start Animation: colored, flat shaded