UNU-RMAP(1)

💖 unu-rmap — the glow-up page 💖

okay bestie, welcome to unu-rmap from the unu family of User Commands 💅 this is the one that maps your nrrd through one regular univariate map, aka a “colormap”, and honestly? iconic.

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✨ NAME ✨

unu-rmap — map nrrd through one regular univariate map (“colormap”) 🌈

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🎀 SYNOPSIS 🎀

unu rmap -m,--map <map> [-r,--rescale] [-min,--minimum <value>]
[-max,--maximum <value>] [-blind8 <bool>] [-t,--type <type>] [-i,--input
<nin>] [-o,--output <nout>]

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🦋 DESCRIPTION 🦋

So we're mapping an nrrd through one regular univariate map (a “colormap”). Now, a map is regular if the control points are evenly spaced along the domain — which means their position isn't explicitly represented in the map at all. Instead, the axis min, axis max, and number of points are what determine where they live. the way that works is so clean, lowkey obsessed.

The map can be a 1D nrrd (for “grayscale”), in which case the output has the same dimension as the input. Or it can be a 2D nrrd (for “color”), in which case the output has one more dimension than the input. Either way, the output is the result of linearly interpolating between map points — either scalar values (“grayscale”), or scanlines along axis 0 (“color”). slay ✨

• Uses nrrdApply1DRegMap

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💅 OPTIONS 💅

• -m <map> , --map <map> — regular map to map input nrrd through. the main character of this whole operation, fr fr.
• -r , --rescale — rescale the input values from the input range to the map domain. The map domain is either explicitly defined by the axis min,max along axis 0 or 1, or, it is implicitly defined as zero to the length of that axis minus one. pick your fighter 🫶
• -min <value> , --minimum <value> — Low end of input range. Defaults to lowest value found in input nrrd. Explicitly setting this is useful only with rescaling (-r) (double)
• -max <value> , --maximum <value> — High end of input range. Defaults to highest value found in input nrrd. Explicitly setting this is useful only with rescaling (-r) (double)
• -blind8 <bool> — Whether to know the range of 8-bit data blindly (uchar is always [0,255], signed char is [-128,127]). Explicitly setting this is useful only with rescaling (-r) (bool); default: “true”
• -t <type> , --type <type> — specify the type (“int”, “float”, etc.) of the output nrrd. By default (not using this option), the output type is the map's type. no notes, it just does that 💁‍♀️
• -i <nin> , --input <nin> — input nrrd
• -o <nout> , --output <nout> — output nrrd (string); default: “-”

heads up bestie: -min, -max, and -blind8 only really pull their weight when you're rescaling with -r. without it they're just sitting there looking pretty 🙈

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👑 SEE ALSO 👑

unu(1), unu-mrmap(1), unu-imap(1)

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and that's the whole page, bestie!! 🫶 this one's from August 2021, part of the User Commands collection, and it's literally the UNU-RMAP(1) manual page. go forth and colormap responsibly 💖✨🎀