Kalibr supports the following projection models:

• pinhole camera model (pinhole)¹
  (intrinsics vector: [fu fv pu pv])
• omnidirectional camera model (omni)²
  (intrinsics vector: [xi fu fv pu pv])
• double sphere camera model (ds)³
  (intrinsics vector: [xi alpha fu fv pu pv])
• extended unified camera model (eucm)⁴
  (intrinsics vector: [alpha beta fu fv pu pv])

The intrinsics vector contains all parameters for the model:

• fu, fv: focal-length
• pu, pv: principal point
• xi: mirror parameter (only omni)
• xi, alpha: double sphere model parameters (only ds)
• alpha, beta: extended unified model parameters (only eucm)

Kalibr supports the following distortion models:

• radial-tangential (radtan)^*
  (distortion_coeffs: [k1 k2 r1 r2])
• equidistant (equi)^**
  (distortion_coeffs: [k1 k2 k3 k4])
• fov (fov)⁵
  (distortion_coeffs: [w])
• none (none)
  (distortion_coeffs: [])

Please cite the appropriate papers when using this toolbox or parts of it in an academic publication.

1. J. Kannala and S. Brandt (2006). A Generic Camera Model and Calibration Method for Conventional, Wide-Angle, and Fish-Eye Lenses, IEEE Transactions on Pattern Analysis and Machine Intelligence, vol. 28, no. 8, pp. 1335-1340

2. Mei, Christopher, and Patrick Rives. "Single view point omnidirectional camera calibration from planar grids." Proceedings 2007 IEEE International Conference on Robotics and Automation. IEEE, 2007.

3. Usenko, Vladyslav, Nikolaus Demmel, and Daniel Cremers. "The double sphere camera model." 2018 International Conference on 3D Vision (3DV). IEEE, 2018.

4. Khomutenko, Bogdan, Gaëtan Garcia, and Philippe Martinet. "An enhanced unified camera model." IEEE Robotics and Automation Letters 1.1 (2015): 137-144.

5. Devernay, Frederic, and Olivier Faugeras. "Straight lines have to be straight." Machine vision and applications 13.1 (2001): 14-24.