EZCALIB

Camera(s) calibration toolbox.

Currently implemented distortion models:

• Radial 1 coef. : k1

• Radial 2 coef. : k1, k2

• Radial 3 coef. : k1, k2, k3

• Radial-Tangential 4 coef. : k1, k2, p1, p2

• Radial-Tangential 5 coef. : k1, k2, k3, p1, p2

• Radial-Tangential 8 coef. : k1, k2, k3, k4, k5, k6, p1, p2

• Kannala-Brandt (large FOV) model : k1, k2, k3, k4

Multi-camera calibration (stereo and N-cameras):

• All cameras are registered with respect to cam0
• At this point, only stereo has been evaluated yet and multi-cameras calibration requires that all cameras have an overlapping view with cam0

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License

EZCalib is released under GPLv3 license.

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Usage

$ ./path/to/ezcalib/build/ezcalib config_file_path.yaml  (optionnal: out_calib_file_path.yaml)

We provide different config files as examples:

• calib_aprilgrid_mono_config.yaml
• calib_chessboard_mono_config.yaml
• calib_chessboard_stereo_config.yaml
• ...

For multi-camera setups, we exepect as input one folder per camera with the same image names for images taken simultaneously. For instance, for a stereo setup you must provide:

• left_cam:

  • image000.png
  • image001.png
  • image002.png
  • ...
  • imageXXX.png

• right_cam:

  • image000.png
  • image001.png
  • image002.png
  • ...
  • imageXXX.png

Where each pair of imageXXX.png from the different folders will be considered as a stereo pair (i.e. images taken simultaneously).

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Dependencies

• OpenCV 3 or 4
• Ceres (v2.1 or higher) : https://github.com/ceres-solver/ceres-solver
• Sophus : https://github.com/strasdat/Sophus

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Install

For convenience, we provide a script to build the application:

$ chmod +x build.sh
$ ./build.sh

If you wish to use your own version of Opencv, Ceres and Sophus, you can skip this step and build manually:

$ mkdir build
$ cd build
$ cmake ..
$ make -j$(nproc)

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To come

• More images input (videos, rosbags, ...)
• Better multi-camera calibration