%=======================================================================
% Copyright 2008-2015, LEGI UMR 5519 / CNRS UJF G-INP, Grenoble, France
% http://www.legi.grenoble-inp.fr
% Joel.Sommeria - Joel.Sommeria (A) legi.cnrs.fr
%
% This file is part of the toolbox UVMAT.
%
% UVMAT is free software; you can redistribute it and/or modify
% it under the terms of the GNU General Public License as published
% by the Free Software Foundation; either version 2 of the license,
% or (at your option) any later version.
%
% UVMAT is distributed in the hope that it will be useful,
% but WITHOUT ANY WARRANTY; without even the implied warranty of
% MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
% GNU General Public License (see LICENSE.txt) for more details.
%=======================================================================
%go_calib_optim
%
%Main calibration function. Computes the intrinsic andextrinsic parameters.
%Runs as a script.
%
%INPUT: x_1,x_2,x_3,...: Feature locations on the images
% X_1,X_2,X_3,...: Corresponding grid coordinates
%
%OUTPUT: fc: Camera focal length
% cc: Principal point coordinates
% alpha_c: Skew coefficient
% kc: Distortion coefficients
% KK: The camera matrix (containing fc and cc)
% omc_1,omc_2,omc_3,...: 3D rotation vectors attached to the grid positions in space
% Tc_1,Tc_2,Tc_3,...: 3D translation vectors attached to the grid positions in space
% Rc_1,Rc_2,Rc_3,...: 3D rotation matrices corresponding to the omc vectors
%
%Method: Minimizes the pixel reprojection error in the least squares sense over the intrinsic
% camera parameters, and the extrinsic parameters (3D locations of the grids in space)
%
%Note: If the intrinsic camera parameters (fc, cc, kc) do not exist before, they are initialized through
% the function init_intrinsic_param.m. Otherwise, the variables in memory are used as initial guesses.
%
%Note: The row vector active_images consists of zeros and ones. To deactivate an image, set the
% corresponding entry in the active_images vector to zero.
%
%VERY IMPORTANT: This function works for 2D and 3D calibration rigs, except for init_intrinsic_param.m
%that is so far implemented to work only with 2D rigs.
%In the future, a more general function will be there.
%For now, if using a 3D calibration rig, set quick_init to 1 for an easy initialization of the focal length
if ~exist('rosette_calibration','var')
rosette_calibration = 0;
end;
if ~exist('n_ima'),
data_calib; % Load the images
click_calib; % Extract the corners
end;
check_active_images;
check_extracted_images;
check_active_images;
desactivated_images = [];
recompute_extrinsic = (length(ind_active) < 100); % if there are too many images, do not spend time recomputing the extrinsic parameters twice..
if (rosette_calibration)
%%% Special Setting for the Rosette:
est_dist = ones(5,1);
end;
%%% MAIN OPTIMIZATION CALL!!!!! (look into this function for the details of implementation)
go_calib_optim_iter;
if ~isempty(desactivated_images),
param_list_save = param_list;
fprintf(1,'\nNew optimization including the images that have been deactivated during the previous optimization.\n');
active_images(desactivated_images) = ones(1,length(desactivated_images));
desactivated_images = [];
go_calib_optim_iter;
if ~isempty(desactivated_images),
fprintf(1,['List of images left desactivated: ' num2str(desactivated_images) '\n' ] );
end;
param_list = [param_list_save(:,1:end-1) param_list];
end;
%%%%%%%%%%%%%%%%%%%% GRAPHICAL OUTPUT %%%%%%%%%%%%%%%%%%%%%%%%
%graphout_calib;