Utah nrrd utilities command-line interface
"teem-unu" is a command-line interface to much of the functionality in "nrrd",
a C library for raster data processing. Nrrd is one library in the "Teem" collection of libraries. More information about Teem is at <http://teem.sf.net>.
Users are strongly encouraged to join the teem-users mailing list:
<http://lists.sourceforge.net/lists/listinfo/teem-users>. This is the primary forum for feedback, questions, and feature requests.
The utility of unu is mainly as a pre-processing tool for getting data
into a type, encoding, format, or dimensions best suited for some visualization or rendering task. Also, slices and projections are effective ways to visually inspect the contents of a dataset. Especially useful commands include make, resample, crop, slice, project, histo, dhisto, quantize, and save. Full documentation for each command is shown by typing the command alone, e.g., "unu make". Unu can process CT and MRI volume datasets, grayscale and color images, time-varying volumes of vector fields (5-D arrays), and more. Currently supported formats are plain text files (2-D float arrays), NRRD, VTK structured points, and PNG and PNM images. "unu make -bs -1" can read from DICOM files. "unu save" can generate EPS files. Supported encodings are raw, ascii, hex, gzip, and bzip2.
Much of the functionality of unu derives from chaining multiple
invocations together with pipes ("|"), minimizing the need to save out intermediate files. For example, if "data.raw.gz" is a gzip'ed 256 x 256 x 80 volume of raw floats written from a PC, then the following will save to "zsum.png" a histogram equalized summation projection along the slowest axis:
unu make -i data.raw.gz -t float -s 256 256 80 -e gzip -en little \
| unu project -a 2 -m sum \ | unu heq -b 2000 -s 1 \ | unu quantize -b 8 -o zsum.png
If unu or nrrd repeatedly proves itself useful for your research, an
acknowledgment to that effect in your publication would be greatly appreciated, such as (for LaTeX): "Dataset processing performed with the {\tt unu} tool (or the {\tt nrrd} library), part of the {\tt Teem} toolkit available at {\tt $<$http://teem.sf.net$>$}"
Formats available: nrrd pnm png vtk text eps Nrrd data encodings available: raw ascii hex gz bz2
The full documentation for teem-unu is maintained as a Texinfo manual. If the info and teem-unu programs are properly installed at your site, the command
info teem-unu
should give you access to the complete manual.