VolumeRendering

Ring Artifacts

Pre- and Post- Classification | | Preintegration

Observation: With non-linear TF in combination with high opacities ring artifacts occur.

Ring1
  • Reason #1: the sampling rate is too low, to capture the non-linear change of the TF from one voxel to another.
  • Reason #2: the approximating assumptions for the numnerical integration do not hold for high opacities.

Solution: oversampling of voxels!

2-times and 4-times oversampling:

Ring2 Ring3

Problem: required oversampling factor is proportional to the maximum absolute value of the derivative of the TF! → bad performance drop

Pre- and Post- Classification | | Preintegration

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