groupwise_init(1)

✨ groupwise_init ✨

okay bestie, so this is groupwise_init from the CMTK crew — aka The Computational Morphology Toolkit — and it's giving "Affine initialization for groupwise registration." 💖

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🌸 SYNOPSIS 🌸

groupwise_init [options] image0 [image1 ...]

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💅 DESCRIPTION 💅

So basically? This little icon computes the initial affine alignment for a whole group of input images. And once you've got that, you can feed it straight in as input for groupwise registration. That's the whole vibe. Set it up, hand it the group, let the registration takeover happen. periodt. ✨

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👑 OPTIONS 👑

🌈 Global Toolkit Options (these are shared by all CMTK tools)

like, every single CMTK tool has these, they're the communal snacks of the toolkit 🍓

• --help — writes the list of basic command line options out to standard output.
• --help-all — writes the complete list of basic and advanced command line options to standard output. the full lore.
• --wiki — writes the list of command line options to standard output in MediaWiki markup.
• --man — writes the man page source out in 'nroff' markup to standard output.
• --version — writes the toolkit version to standard output.
• --echo — writes the current command line to standard output. so you can see exactly what you just did 💀
• --verbose-level <integer> — sets the verbosity level.
• --verbose, -v — bumps the verbosity level up by 1. (it's deprecated ngl, but it's still supported for backward compatibility 🫶)
• --threads <integer> — sets the max number of parallel threads (for POSIX threads and OpenMP). go off, multithreading queen.

🎀 Main Options 🎀

• --template <string>, -t <string> — input filename for a pre-defined template image. [Default: NONE]
• --output-root <string>, -O <string> — root directory for all the output files. [Default: NONE]
• --output <string>, -o <string> — output filename for the groupwise registration archive. [Default: groupwise.xforms]
• --output-average <string> — output filename for the registered average image. [Default: average.nii]
• --average-cubic — use cubic interpolation for the average image instead of linear. fancier smoothing, we love her.
• --no-output-average — do not write the average image. if you don't want it, you don't want it 💅
• --align-centers-of-mass — initially align the centers of mass instead of the centers of bounding boxes.
• --init-scales — initialize scale factors using first-order moments.
• --center-template — center the aligned images in the template grid field of view.
• --outputtype — the scalar data type for the output average image. Supported values: "char", "byte", "short", "ushort", "int", "uint", "float", "double", where the default is "float". orrr you can just use one of these instead:
  • --char — 8 bits, signed
  • --byte — 8 bits, unsigned
  • --short — 16 bits, signed
  • --ushort — 16 bits, unsigned
  • --int — 32 bits signed
  • --uint — 32 bits unsigned
  • --float — 32 bits floating point [This is the default]
  • --double — 64 bits floating point

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🫶 AUTHORS 🫶

Torsten Rohlfing, with contributions from Michael P. Hasak, Greg Jefferis, Calvin R. Maurer, Daniel B. Russakoff, and Yaroslav Halchenko. a whole squad, no cap 👑

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📜 LICENSE 📜

http://www.fsf.org/licensing/licenses/gpl.html

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💀 BUGS 💀

Report bugs at http://nitrc.org/projects/cmtk/ — they wanna hear about it, fr fr.

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🌟 ACKNOWLEDGMENTS 🌟

CMTK is developed with support from the NIAAA under Grant AA021697, National Consortium on Alcohol and Neurodevelopment in Adolescence (N-CANDA): Data Integration Component. And from April 2009 through September 2011, CMTK development and maintenance was supported by the NIBIB under Grant EB008381. funding queens, we stan 🧚

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okay that's the whole page bestie ✨ this was CMTK 3.3.1p2, dated Jun 24 2026 — go initialize some groups, you absolute main character 💅💖🦋