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Interpolate Point Cloud to Regular Grid

Group (Subgroup)

Sampling (Interpolation)

Description

This Filter interpolates the values of arrays stored in a Vertex Geometry onto a user-selected Image Geometry. The use defines the (x,y,z) radii of a kernel is real space units. This kernel can be intialized to either uniform or Gaussian. The interpolation algorithm proceeds as follows:

  1. The kernel radii defined by the user in real space units are converted into voxel units, based on the spacing of the supplied Image Geometry.
  2. The kernel is centered on each vertex in the Vertex Geometry.
  3. The values of each Attribute Array on the centered vertex are associated to each voxel intersected by the kernel. This stored value is multiplied by the value of the kernel.

The result of the above approach is a list of data at each voxel in the Image Geometry for each interpolated Attribute Array. These lists may be of different lengths within each voxel, since the kernels from each point may overlap. This duplication may result in significant memory usage if the number of points is large; the user may select a subset of arrays to interpolate to alleviate this issue. Note that all arrays selected for interpolation must be scalar.

A mask may be supplied to the filter. Points that are not within the mask are ignored during interpolation. Additionally, the distances between each voxel and the source point for the intersecting kernel may be stored; this significantly increases the required memory. Arrays may be passed through to the image geometry without applying any interpolation. This operation is equivalent to used a uniform kernel.

Parameters

Name Type Description
Use Mask bool Whether to use a mask when interpolating the vertex arrays
Store Kernel Distances bool Whether to store the kernel distances for each vertex
Interpolation Technique Enumeration The type of kernel to use, either Uniform or Gaussian
Kernel Size float 3x The size of the interpolation kernel, in real space units

Required Geometry

Vertex and Image

Required Objects

Kind Default Name Type Component Dimensions Description
Data Container None N/A N/A Data Container holding the Vertex Geometry to interpolate
Data Container None N/A N/A Data Container holding the Image Geometry that serves as the target grid for interpolation
Vertex Attribute Array VoxelIndices size_t (1) The indices that indicate in which voxel in the supplied Image Geometry each vertex lies
Various Attribute Array None Varies (1) The Vertex Attribute Arrays to interpolate
Various Attribute Array None Varies (1) The Vertex Attribute Arrays to copy

Created Objects

Kind Default Name Type Component Dimensions Description
Attribute Matrix InterpolatedAttributeMatrix Cell N/A Attribute Matrix that stores the interpolated Attribute Arrays

Please see the description file distributed with this plugin.

DREAM3D Mailing Lists

If you need more help with a filter, please consider asking your question on the DREAM3D Users mailing list: https://groups.google.com/forum/?hl=en#!forum/dream3d-users