Export
The Export page allows you to write project content to external file formats. Exports enable data sharing with external applications, preparation for 3D printing, input for simulation software, medical imaging system integration, and documentation generation.
Export operations work on the currently selected or active object. Before exporting, verify that the correct volume, mask, surface, or mesh is selected in the Object Browser.
Available Export Types
| Export Type | Description |
|---|---|
| Volume Image | Export volume data to standard 3D formats |
| Volume Image as Image Stack | Export volume slices as 2D image sequences |
| Volume Image as Video | Export slice-through animation as video |
| Volume Image as DICOM Images | Export volume data to DICOM format |
| Mask Image | Export mask/segmentation data to 3D formats |
| Surface Model | Export surface meshes to CAD/STL/3D formats |
| Volume Mesh Model | Export tetrahedral/hexahedral meshes |
| 3D Scene | Export scene including measurements and annotations |
Exporting Volume Images
Export the active volume to standard 3D volume formats for use in other analysis applications.
Workflow
- Select the volume to export in the Object Browser
- Navigate to File → Export → Volume Image
- Click the large icon to open the file dialog
- Choose the output format and location
- Click Save to export
Supported Formats
| Format | Extensions |
|---|---|
| Meta Image | .mha, .mhd |
| NIfTI | .nii, .nii.gz |
| NRRD | .nrrd, .nhdr |
| Analyze | .hdr, .img.gz |
| GIPL | .gipl |
| LSM | .lsm |
| VTK Image | .vti |
NIfTI stores voxel spacing and origin as single precision numbers, so exporting to .nii or .nii.gz rounds those values. Importing the file back gives geometry that differs slightly from the original, which is enough to be reported as a geometry mismatch at the default origin comparison of six decimal places.
Use Meta Image (.mha, .mhd) or NRRD when the geometry has to round-trip exactly. Both store spacing and origin as text at full precision. See Import for the workaround if NIfTI is required.
Meta Image .mhd, NRRD .nhdr, and Analyze .hdr store the header and the voxel data in separate files. The data file is written next to the header with the same base name, and the header refers to it by name only. Keep the pair together when moving or sharing the export. Choose .mha or .nrrd for a single self-contained file.
Exporting Volume as Image Stack
Export volume slices as a sequence of 2D images. This is useful for documentation, external 2D image processing, or creating input for systems that accept image sequences.
The image-stack export dialog is also reused by Image → Reslice → Export All Slices. In that case it exports the current resliced preview volume instead of the original active volume. The control layout is the same, but the source data and export semantics are described in Reslice.
Workflow
- Select the volume to export
- Navigate to File → Export → Volume Image as Image Stack
- Click the large icon to open the export dialog
- Choose the slice plane to export
- Choose whether to export the current slice, all slices, or a range
- If needed, define the range and increment
- Enter the base file name, output format, and destination folder
- Click Apply to export
Image Stack Export Dialog Controls
| Control | Description |
|---|---|
| Slice plane | Chooses which orthogonal stack to export. Plane 1 (YZ) exports slices orthogonal to the X axis, Plane 2 (XZ) exports slices orthogonal to the Y axis, and Plane 3 (XY) exports slices orthogonal to the Z axis. |
| Current | Exports only the current slice for the selected plane. |
| All | Exports the full stack for the selected plane. |
| Range | Enables the range controls so you can export only part of the stack. |
| From | Start slice position for a range export. The values are shown in physical slice spacing units for the selected plane. |
| Until | End slice position for a range export. |
| Increment | Slice step for range export. 1 exports every slice, 2 exports every second slice, and so on. |
| Count | Read-only preview of how many images will be written using the current plane, range, and increment settings. |
| File name | Base file name used to generate the exported image filenames. The active volume label is prefixed automatically. |
| Format | Output image format. Available formats are bmp, jpg, and png. |
| Path | Destination folder for the exported image series. |
| Browse... | Opens a folder picker for the export destination. |
| Apply | Starts writing the image series to disk. |
| Close | Closes the dialog without starting a new export. |
Behavior Notes
- File-tab image-stack export writes slices from the original active volume data.
- The dialog validates that the destination folder exists before export starts.
- If Range is selected, From must not be after Until.
- The dialog updates Count automatically when the plane, range, or increment changes.
Output Structure
Images are named with the base name plus a sequential number:
BaseName_001.png
BaseName_002.png
BaseName_003.png
...
The dialog displays a count of images that will be exported based on your settings. Verify this count before exporting to avoid generating excessive files.
Exporting Volume as Video
Create a video that sweeps through volume slices—useful for presentations, documentation, or sharing with stakeholders who don't have volume visualization software.
Workflow
- Select the volume to export
- Navigate to File → Export → Volume Image as Video
- Click the large icon to open the export dialog
- Configure export parameters:
| Parameter | Options | Description |
|---|---|---|
| Plane | Plane 3 (XY), Plane 2 (XZ), Plane 1 (YZ) | Slice sweep orientation |
| FPS | 1–240 | Frames per second |
| Format | AVI, MP4 (H.264) | Output video format |
- Select the output file path
- Click OK to export
- A progress dialog shows export status
Considerations
- Video duration = (number of slices) / FPS
- Higher FPS creates smoother but faster playback
- MP4 with H.264 provides better compression than AVI
Exporting Volume as DICOM
Export volume data to DICOM format for integration with medical imaging systems or PACS.
Workflow
- Select the volume to export
- Navigate to File → Export → Volume Image as DICOM Images
- Configure DICOM export settings (patient information, study details)
- Select the output folder
- Click OK to export
Volvicon is not a regulated medical device. DICOM exports from Volvicon should not be used for clinical diagnosis or treatment without validation by qualified professionals using approved systems.
Exporting Mask Images
Export segmentation masks to 3D volume formats. Masks are exported as label maps where each label value represents a distinct region.
Workflow
- Select the mask to export in the Object Browser
- Navigate to File → Export → Mask Image
- Click the large icon to open the file dialog
- Choose the output format and location
- Click Save to export
Supported Formats
| Format | Extensions |
|---|---|
| Meta Image | .mha, .mhd |
| NIfTI | .nii, .nii.gz |
| VTK Image | .vti |
Masks are written as label images with one value per voxel and 0 as background. A mask exported from Volvicon can be imported back through File → Import → 3D Images as Masks.
Exporting Surface Models
Export surface meshes for 3D printing, CAD integration, or visualization in other applications.
Workflow
- Select the surface(s) to export in the Object Browser
- Navigate to File → Export → Surface Model
- Click the large icon to open the export dialog
- Select the output format
- Configure format-specific options if available
- Choose the output location and click Save
Supported Formats
| Format | Extension | Use Case |
|---|---|---|
| STL | .stl | 3D printing, CAD import |
| PLY | .ply | Mesh exchange with vertex colours |
| OBJ | .obj | General 3D graphics |
| 3MF | .3mf | Modern 3D printing with color and material |
| U3D | .u3d | PDF embedding, 3D documentation |
| AMF | .amf | Additive manufacturing |
| VRML | .wrl | Web 3D, legacy visualization |
| glTF | .gltf | Web and real-time 3D |
| X3D | .x3d | Web 3D successor to VRML |
| Open Inventor | .iv | Legacy scene exchange |
| STEP Triangles | .step | CAD exchange as a tessellated shape |
| IGES Triangles | .iges | CAD exchange as a tessellated shape |
| VTP | .vtp | VTK poly data |
| Points | .xyz | Vertex positions only, no faces |
| 3D PDF | .pdf | Interactive document, produced by a separate dialog |
The save dialog offers STL and PLY in both ASCII and binary variants. When a file name is typed without a recognised extension, the extension of the selected filter is appended.
Format Considerations
- STL: Universally supported for 3D printing, ASCII or binary variants
- 3MF: Supports multiple objects, colors, and materials in a single file
- U3D: Can be embedded in PDF documents for interactive 3D viewing
- PLY and OBJ: Good for graphics applications, may include vertex colors
- STEP and IGES: Written as tessellated triangles, not as analytic CAD surfaces, so the result is a mesh rather than editable CAD geometry
- XYZ: Writes vertex positions only, so faces are lost
Volvicon reads .glb but writes the text form only. Export to .gltf.
For 3D printing, verify that the exported mesh is watertight (no holes) and has correct normals. Use Diagnostics and Fixes before exporting if mesh quality is uncertain.
Exporting Volume Meshes
Export tetrahedral or hexahedral meshes for finite element analysis or simulation software.
Workflow
- Select the volume mesh in the Object Browser
- Navigate to File → Export → Volume Mesh Model
- Select the output format appropriate for your simulation tool
- Choose the output location and click Save
Supported Formats
| Format | Extension |
|---|---|
| VTK Unstructured Grid | .vtu (ASCII or binary) |
| VTK | .vtk (ASCII or binary) |
Solver formats such as Abaqus, Nastran, LS-DYNA, ANSYS, Gmsh, and OpenFOAM are written from the FEM Mesh Export tools rather than from this page, because they need the part, set, and material information that those tools collect.
Exporting 3D Scenes
Export the entire scene including multiple objects, measurements, and annotations to consolidated 3D formats. This is useful for creating interactive documentation or sharing complete analysis results.
Workflow
- Set up the scene with desired visibility and arrangement
- Navigate to File → Export → 3D Scene
- Select the output format (3MF, U3D, VRML)
- Configure options if available
- Choose the output location and click Save
What's Included
- Visible surfaces with their current colors/materials
- Measurements and annotations (where format supports)
- Scene positioning and arrangement
Not all scene elements may be supported by all export formats. Complex annotations may be simplified or omitted depending on the target format's capabilities.
How Exports Are Written
An existing file is replaced only by a complete one
Every file export is written to a temporary location first and moved onto the destination only after the writer reports success. If an export fails or is cancelled part way through, the previous file at that location is left untouched and no partial file is created. Formats that write a header and a separate data file are moved together, so the pair can never end up half replaced.
Because the temporary location is a subfolder of the destination folder, the destination has to allow subfolders to be created. A destination that permits files but not folders, which occurs on some network shares, causes the export to fail without writing anything.
File naming
When several objects are exported to a folder at once, each file is named after its object.
- Characters that cannot appear in a file name are replaced with an underscore
- Names that would otherwise be reserved by the operating system are prefixed with an underscore
- Objects that would produce the same file name are given a numeric suffix, for example
Femur,Femur_1,Femur_2
Batch results
A batch export reports success only when every requested object was written. An object holding no usable data is named in the log and skipped, and the operation reports failure so a partially completed export is never mistaken for a complete one.
Best Practices
Before Exporting
- Select the correct object: Verify the intended object is selected/active
- Check object visibility: Some exports respect visibility settings
- Verify data quality: Run diagnostics on surfaces before export
Coordinate Systems
- Exports maintain the coordinate system used in Volvicon
- Verify coordinate system compatibility with the receiving application
- Document the coordinate convention when sharing data
File Naming
Use descriptive filenames that include:
- Subject/sample identifier
- Data type (volume, surface, mesh)
- Processing state (raw, segmented, smoothed)
- Date or version number
Validation
After exporting:
- Verify the exported file opens correctly in the target application
- Check that dimensions and scale are correct
- Confirm that all expected data is present
Troubleshooting
Export Produces Empty or Invalid File
- Verify an object is selected before exporting
- Check that the selected object contains data
- Try a different output format
Export Reports Failure and Nothing Is Written
- Confirm the destination folder exists and allows both files and subfolders to be created. A network share that blocks subfolders prevents the staged write used by every export.
- Confirm no other application is holding the destination file open.
- Check the log for the name of the object that could not be written.
A Re-Imported File Is Reported as Mismatched
This is expected for NIfTI, which stores voxel spacing and origin as single precision numbers and therefore rounds them on export. Use Meta Image or NRRD when the geometry has to round-trip exactly, or lower Origin comparison precision in Preferences → Import.
Typed File Name Was Given a Different Extension
If the typed name does not end with an extension the selected format recognises, the extension of the chosen filter is appended. A name such as CT 1.5mm is saved as CT 1.5mm.mha when the Meta Image filter is selected.
Exported Surface Has Inverted Normals
- Run Diagnostics and Fixes to correct normals before export
- Some applications can flip normals on import
Video Export Fails
- Verify sufficient disk space for the output file
- Check that the output path is writable
- Try a different video format
DICOM Export Not Accepted by Target System
- Verify the target system accepts third-party DICOM files
- Check that required DICOM tags are populated
- Consult with your imaging IT department for compatibility requirements
Related Topics
- Import - Importing data from external sources
- Save - Saving the Volvicon project file
- Record Video - Capturing screen recordings
- Save Screenshot - Capturing static images