NRRD

NRRD for Volume Visualization

Nearly Raw Raster Data (NRRD a.k.a. 'Nerd') is a data format and toolset for representing volume data.

The NRRD website includes extensive details, examples, conversion utilities, resources, and references.

NRRD and the corresponding team software library facilitates the pre-processing tasks (cropping, quantizing, resampling) of volume data. It also helps with the basic analysis tasks which help to understand the structure of a dataset (histograms, maximum intensity projections, connected components).

In addition to the teem library and codebase, several important tools support the processing and use of NRRD volume data format as well as DICOM:

• ImageJ
• Seg3D
• ITKSnap
• Slicer

The X3D Volume Rendering component defines how to describe the presentation of volumetric data in interactive 3D scenes. These capabilities were approved in X3D version 3.3. Support for the NRRD format is optional for X3D players. For more details on processing pipelines, see the Web3D 2013 Tutorial!

The X3D Basic Examples - Volume Visualization provides example X3D scenes utilizing NRRD. These scenes have been prepared by the Virginia Tech (VT) Visual Computing Group research group and published under an open-source license.

Possibilities for Future Work

• Continue exercising improving tool-chain support and options for creating and integrating volume data in X3D scenes
• Outreach to NRRD community regarding relevant X3D capabilities and collaboration opportunities
• Continue evaluation of whether other volume formats with similar capabilities are available
  • Volume data format by Paul Bourke
  • OpenQVis Volume File Format
  • VolDat format for exchanging volume data
  • Uvf - Unified Volume Format
  • Space Volume native file format specification by Space Software
  • Stanford volume data archive
  • Perhaps conventions for using TIFF to consistently record image slices
• Consider suitability of NRRD to be added as part of a collection of standards (DICOM, X3D, others) for archival medical records
• Assess whether NRRD maturity is sufficient to initiate standardization efforts by Web3D Consortium for the International Organization for Standardization (ISO)