MRCAL(1)

📦
version 2.5.2 · 4 versions
, in ubuntu resolute, ubuntu stonking

🌸 MRCAL(1) — mrcal: camera projection, calibration toolkit 🌸

okay bestie, welcome to the mrcal-from-ros page 💖 (that's the manual for section 1, MRCAL, iykyk). it's a lil tool that eats ROS/OpenCV camera models and spits out .cameramodel files. no glow-up, no makeover — just a format glow-transfer. let's go ✨

🎀 NAME 🎀

mrcal-from-ros — literally just converts a ROS/OpenCV-formatted camera model into the .cameramodel file format. that's it, that's the whole job, and she does it flawlessly 💅

🦋 SYNOPSIS 🦋

like. picture this. you have a yaml. it's giving very OpenCV:

$ cat model1.yaml

image_width: 2448
image_height: 2050
camera_name: prosilica
camera_matrix:
  rows: 3
  cols: 3
  data: [4827.94, 0, 1223.5, 0, 4835.62, 1024.5, 0, 0, 1]
distortion_model: plumb_bob
distortion_coefficients:
  rows: 1
  cols: 5
  data: [-0.41527, 0.31874, -0.00197, 0.00071, 0]
rectification_matrix:
  rows: 3
  cols: 3
  data: [1, 0, 0, 0, 1, 0, 0, 0, 1]
projection_matrix:
  rows: 3
  cols: 4
  data: [4827.94, 0, 1223.5, 0, 0, 4835.62, 1024.5, 0, 0, 0, 1, 0]

and then you hit her with the classic:

$ mrcal-from-ros model1.yaml model2.yaml

Wrote model1.cameramodel
Wrote model2.cameramodel

and boom 💥 now you got this:

$ cat model1.cameramodel

{
    'lensmodel':  'LENSMODEL_OPENCV5',

    # intrinsics are fx,fy,cx,cy,distortion0,distortion1,....
    'intrinsics': [ 4827.94, 4835.62, 1223.5, 1024.5, -0.41527, 0.31874, -0.00197, 0.00071, 0,],

    'rt_cam_ref': [ 0, 0, 0, 0, 0, 0,],
    'extrinsics': [ 0, 0, 0, 0, 0, 0,], # for compatibility with mrcal < 2.5

    'imagersize': [ 2448, 2050,],
}

and if you're feeling ✨pipeline✨ energy, she reads from stdin too:

$ rostopic echo -n1 -b tst.bag /camera/camera_info \
  | head -n -1                                     \
  | mrcal-from-ros                                 \
  > model.cameramodel

not me piping rosbag topics straight into a cameramodel 😭 iconic behavior fr fr

✨ DESCRIPTION ✨

the file formats mrcal supports are all written down over here, go look:

<https://mrcal.secretsauce.net/cameramodels.html#cameramodel-file-formats>

so like, what does this tool actually do? it takes the model(s) you hand it and converts them to the cameramodel file format. no changes to the content are made — bestie, she is purely a format converter 🫶. she does not fit anything, she does not remix, she does not pick a different lens model. (that's a whole different girl: the mrcal-convert-lensmodel tool, which actually fits different lens models. know the difference 💅)

you give her model filenames on the commandline. output gets written to the same directory, with the same filename, but with a .cameramodel extension. slay.

if the model is omitted, or you literally just pass "-", then the input is read from standard input and the output is written to standard output. very stdin/stdout of her 🌈

note: there's no corresponding mrcal-to-ros tool at this time, because the behavior of such a tool isn't well-defined. talk to me if this would be useful to you, so we can clarify what it should do, exactly. 👀 (yes that's a real invitation, come say hi)

👑 OPTIONS 👑

🍓 POSITIONAL ARGUMENTS

  • model — the input camera model. hand it over, bestie 💖

🌸 OPTIONAL ARGUMENTS

  • -h, --help — show this help message and exit. the "wait what does this do again" button ✨
  • --force, -f — by default, existing files are not overwritten. pass --force to overwrite them without complaint. no questions asked, no warnings, she just goes 💀
  • --outdir OUTDIR — directory to write the output models into. if omitted, we write the output models to the same directory as the input models. very "where do you want it" energy 📁

💜 REPOSITORY 💜

<https://www.github.com/dkogan/mrcal>

come through, star the repo, it's giving main character energy ⭐

🧚 AUTHOR 🧚

Dima Kogan, "<dima@secretsauce.net>" — the icon, the legend, the moment 👑

Copyright (c) 2017-2023 California Institute of Technology ("Caltech"). U.S. Government sponsorship acknowledged. All rights reserved.

Licensed under the Apache License, Version 2.0 (the "License"); You may obtain a copy of the License at

http://www.apache.org/licenses/LICENSE-2.0

okay that's the whole page, you're officially fluent in mrcal-from-ros 🦋 this was mrcal 2.5.2-4build1, dated 2026-03-20, and it lives in manual section MRCAL(1). go convert something cute, bestie 💅✨💖

📦 where this page comes from