Skip to content

Export

Export writes an image, or the 3D fields a result saved, to a file you download: a voxel image or a field for ParaView, a surface mesh for CAD or 3D printing, or an archive of arrays for your own scripts.

  • Find it Tools › Image Management › Export, Download image on an image's page, or Download scalar fields on a result's page
  • Takes an image or a batch, or a completed result that saved fields
  • Returns a file to download: VTK image data, an STL mesh or a NumPy archive, or a Zarr archive
  • Runs on CPU

Run it

To export an image:

  1. Open Tools, then Image Management, and select Export. Download image on an image's page opens the same form with the image chosen.
  2. Under Source, choose the Image, or a batch to export every image in it.
  3. Under Output, choose the Export Format, and the options that appear for it.
  4. Select Run. The export runs as a job; when it completes, select Exported image on the job page to download the file.

To export the fields a result saved, such as a velocity or concentration field:

  1. On the result's job page, select Download scalar fields. Or open Export, choose an image, and pick a scalar-field Export Format.
  2. Choose the Analysis result, and tick the Scalar fields you want. All are ticked to start with.
  3. Select Prepare download. Preparation runs in the background, so you can leave the page; the download appears on the same page and in Jobs.
  4. Select Download NPZ or Download VTK, and Field metadata (JSON) for a description of each field and its stored units.

The Export form set to write a VTK image, with its Downsample and Divide options.

VTK image output, with its Downsample and Divide options.

The scalar-field export for a permeability result, with its fields ticked and the NPZ download ready.

Choose the result and its fields; Download NPZ appears once the archive is ready.

Settings

Setting Default Range What it does
Image your team's images and batches What to export.
Export Format VTK Image Data (.vti) see Formats The file to write.
Downsample off on, off VTK image only. Halves the image along each axis before export. Can't be combined with Divide.
Divide off on, off VTK image only. Splits the image at the middle Z slice into two VTK files, downloaded together as a ZIP archive, for very large images. Can't be combined with Downsample.
Meshing method Direct voxel faces Direct voxel faces, Marching cubes STL only. How the surface is built.
Mesh representation OpenSTL OpenSTL, scikit-image, PyVista STL only. The library that writes the mesh; all save a binary STL.
Analysis result completed results that saved fields Scalar fields only. The result whose fields to export.
Scalar fields all the result's fields Scalar fields only. The fields to put in the file.

Formats

The voxel size of the image is written into every VTK file as its spacing, or 1 when the image has none. It's the voxel size at the time of export: correcting it later doesn't change a file you've already downloaded.

VTK Image Data (.vti) — voxel image for ParaView. The image's voxels on a regular grid, for ParaView and other VTK software.

Setting Value
Downsample off, or half size along each axis
Divide off, or two files split at the middle Z slice, in one ZIP archive; not with Downsample
Spacing the image's voxel size

STL Mesh (.stl) — for 3D printing / CAD. The pore–solid surface as a triangle mesh, saved as a binary STL.

Setting Value
Image a segmented image; the other formats take any image
Meshing method the faces of the solid voxels, or a smooth Marching cubes surface
Mesh representation OpenSTL, scikit-image or PyVista

NumPy archive (.npz) — scalar fields. The fields you ticked from one result, one array per field, on the image's grid. Values are written as stored, including the gaps in the solid. A separate JSON file describes each field and its stored units.

Setting Value
Fields any of the result's fields
Available for 24 hours after it's prepared; an expired archive can be prepared again

VTK Image Data (.vti) — scalar fields for ParaView. The same fields as one VTK file, with the image's voxel size as its spacing, ready to open in ParaView or in ParaView Server.

Setting Value
Fields any of the result's fields
Available for 24 hours after it's prepared

Zarr archive (.zarr.zip) — native scalar fields. The stored arrays and their metadata in one ZIP, without conversion or recompression. Open it directly with Zarr, or extract it as a folder. Fields PoreStore derives when you read a result, such as a velocity magnitude, aren't stored and so aren't included; use NPZ or VTK for those.

Setting Value
Fields the result's stored fields
Available for 24 hours after it's prepared

Results

An image export completes as a job, and its page offers Exported image to download the file. A divided VTK export downloads as a ZIP archive of the image's two halves: unzip it and open both files together in ParaView, where each half sits in its place in the image. A field export shows Download NPZ, Download Zarr or Download VTK, with the time it's available until.

A completed Export job with its Exported image download button.

The exported file is under Available Actions.

Common problems

  • A result's fields aren't listed. Only completed results that saved fields can be exported, and a result whose image was saved over, or deleted, no longer has them. Run the analysis again to get its fields back.
  • The archive has expired. Prepared field downloads last 24 hours. Select Prepare download again.
  • ParaView shows the wrong size. The image had no voxel size, so the spacing is 1. Set the voxel size on the image page and export again.
  • The file is too large to open. Turn on Downsample or Divide, not both, or trim the image first.