neuromag_load_mri_info

 load neuromag mri-fiffile.
 [USAGE]
    [voxel, mri_trans_info] = neuromag_load_mri_info(<fiffile>);
 [IN]
    fiffile : neuromag MRI fiffile.
 [OUT]
    voxel              : Voxel data in MRI fiffile. [X x Y x Z uint8]
    mri_trans_info
       .trans_head2mri : [4 x 4 double]
                       : transformation matrix (HEAD ==> MRI(usually DICOM))
       .trans_head2vox : [4 x 4 double]
                       : transformation matrix (HEAD ==> Voxel)
       .trans_vox2mri  : [4 x 4 double]
                       : transformation matrix (VOXEL ==> MRI(usually DICOM))

 rH : position in Head coordinate
 rM : position in MRI coordinate
 rV : position in Voxel coordinate
 
 [rM 1] = [rH 1] * trans_head2mri;
 [rM 1] = [rV 1] * trans_vox2mri;
 [rV 1] = [rH 1] * trans_head2vox;

 Copyright (C) 2011, ATR All Rights Reserved.
 License : New BSD License(see VBMEG_LICENSE.txt)

0001 function [voxel, mri_trans_info] = neuromag_load_mri_info(fiffile)
0002 % load neuromag mri-fiffile.
0003 % [USAGE]
0004 %    [voxel, mri_trans_info] = neuromag_load_mri_info(<fiffile>);
0005 % [IN]
0006 %    fiffile : neuromag MRI fiffile.
0007 % [OUT]
0008 %    voxel              : Voxel data in MRI fiffile. [X x Y x Z uint8]
0009 %    mri_trans_info
0010 %       .trans_head2mri : [4 x 4 double]
0011 %                       : transformation matrix (HEAD ==> MRI(usually DICOM))
0012 %       .trans_head2vox : [4 x 4 double]
0013 %                       : transformation matrix (HEAD ==> Voxel)
0014 %       .trans_vox2mri  : [4 x 4 double]
0015 %                       : transformation matrix (VOXEL ==> MRI(usually DICOM))
0016 %
0017 % rH : position in Head coordinate
0018 % rM : position in MRI coordinate
0019 % rV : position in Voxel coordinate
0020 %
0021 % [rM 1] = [rH 1] * trans_head2mri;
0022 % [rM 1] = [rV 1] * trans_vox2mri;
0023 % [rV 1] = [rH 1] * trans_head2vox;
0024 %
0025 % Copyright (C) 2011, ATR All Rights Reserved.
0026 % License : New BSD License(see VBMEG_LICENSE.txt)
0027 
0028 %
0029 % --- Previous check
0030 %
0031 if ~exist('fiffile', 'var') || exist(fiffile, 'file') ~= 2
0032     error('invalid fiffile was specified.');
0033 end
0034 
0035 %
0036 % --- Get MRI Data
0037 %
0038 hdr = fiff_read_mri(fiffile);
0039 voxel_t = cat(3, hdr.slices.data);
0040 voxel   = permute(voxel_t, [2 1 3]);
0041 
0042 trans_vox2mri  = hdr.voxel_trans.trans;
0043 trans_head2mri = hdr.trans.trans;
0044 
0045 
0046 % [rM 1] = [rH 1] * trans_head2mri';
0047 % [rM 1] = [rV 1] * trans_vox2mri';
0048 % [rV 1] = [rM 1] / trans_vox2mri';
0049 % [rV 1] = [rH 1] * trans_head2vox;
0050 % trans_head2vox = trans_head2mri' / trans_vox2mri';
0051 
0052 mri_trans_info = struct;
0053 mri_trans_info.trans_head2mri = trans_head2mri';
0054 mri_trans_info.trans_head2vox = trans_head2mri' / trans_vox2mri';
0055 mri_trans_info.trans_vox2mri  = trans_vox2mri';