---------------------------------------------------------------------------- From: Reg Willson Subject: Camera Calibration using Tsai's Method - revision 3.0b3 This release of the camera calibration software includes the following changes: 1) source code written entirely in C, 2) Unix and PC/DOS (Borland 4.5) compatibility, 3) cleaner dynamic memory allocation, and 4) a Frequently Asked Questions (FAQ) file and a change log file. The release is available via anonymous ftp from ftp.teleos.com The code and documentation are contained in the files /VISION-LIST-ARCHIVE/SHAREWARE/CODE/CALIBRATION/Tsai-method-v3.0b3.tar.Z /VISION-LIST-ARCHIVE/SHAREWARE/CODE/CALIBRATION/tsai30b3.zip The release is also available via the world wide web at URL http://www.ius.cs.cmu.edu/afs/cs.cmu.edu/user/rgw/www/TsaiCode.html Special thanks to Markus Menke , Franz-Josef L|cke , Piotr Jasiobedzki , Jim Vaughan , Pete Rander , and many others for all their help with the PC/DOS port and bug reports. Comments, suggestions, and bug reports can be directed to me at Reg Willson . Reg Willson, 28-Oct-95 ---------------------------------------------------------------------------- From: Reg Willson Subject: Camera Calibration using Tsai's Method - revision 2.1 This revision includes a fully self contained implementation of Roger Tsai's camera calibration algorithm using *public domain* MINPACK optimization routines (the code may also be built using commercial IMSL optimization routines). Also included is a fix for a bug that reduced the accuracy of full coplanar calibration and increased the convergence time of full non-coplanar calibration. Finally, generic macros have been added for three less common math routines used in the code. Thanks to Torfi Thorhallsson (torfit@verk.hi.is) at the University of Iceland who provided the self contained MINPACK version of the code. Torfi also identified the coplanar calibration bug. Thanks also to Frederic Devernay who also submitted a unified MINPACK/IMSL/NAG version of the calibration code. Future code revisions will likely use Fred's macros for isolating and simplifying the interfaces to the various optimization packages. Also in the works is a PC compatible version of the code. Comments, suggestions, and bug reports can be directed to me at Reg Willson . Reg Willson, 04-Jun-94 ---------------------------------------------------------------------------- From: Reg Willson Subject: Camera Calibration using Tsai's Method - revision 2.0 This software release represents a set of updates to the software placed in the VISLIST ARCHIVE in 1993 by Jon Owen. The release contains a bug fix, improvements to several routines, and new code for exterior orientation calibration. The code should also be much easier to compile than the previous release. The bug fix occurs in the routines ncc_compute_R and ncc_compute_better_R. In the corrected routines the r4, r5, and r6 terms are not divided by cp.sx. This bug was reported by Volker Rodehorst . Included in this release is Frederic Devernay's significantly improved routine for converting from undistorted to distorted sensor coordinates. Rather than iteratively solving a system of two non-linear equations to perform the conversion, the new routine algebraically solves a cubic polynomial in Rd (using the Cardan method). This release also contains improved routines for calculating calibration error statistics, including the new routines: object_space_error_stats () and normalized_calibration_error () The first routine calculates the statistics for the magnitude of the distance of closest approach (i.e. 3D error) between points in object space and the line of sight formed by back projecting the measured 2D coordinates out through the camera model. The second routine is based on an error measure proposed by Weng in IEEE PAMI, October 1992. Finally this release contains new checks for coordinate handedness problems in the calibration data. This release uses optimization routines from the IMSL commercial software package. An updated version of the code set up for the NAG commercial software package will hopefully be available soon. Bug reports can be directed to either Jon or myself. Reg Willson, 17-Feb-94 ---------------------------------------------------------------------------- From: jcowen@cs.utah.edu Subject: Camera Calibration using Tsai's Method Several months ago, I posted to the vision list asking for camera calibration help. One response led me to contact Reg Willson, who was extremely helpful, and sent me his implementation of Roger Tsai's calibration algorithm. He said I could re-distribute it as needed, and we've made it ftp'able from cs.utah.edu. It's in the pub/ReverseEngineering/src/CameraCalibration directory. I'd like to get bug reports, so I can filter them and pass them on to Reg. Also, if anybody replaces the IMSL stuff w/public domain routines, I'd like to know. Thanks, Jon ----------------------------------------------------------------------------