--- Input
meg_dir : MEG data dir
meg_id : MEG system ID
--- Optional Input
param.time_win = [Tstart Tend]: [ms]
param.trials = trial index to extract
param.Pos_chk : if 1, pick are converted to DICOM cordinate.
--- Output:
meg_info : structure with following field
.nch, % number of active gardiometers
.nch0 % number of gardiometers
.nsamp, % sampling number of measurement
.nprsamp, % sampling number for pre-trigger
.sampf, % sampling frequency
.nrept, % repeat number
.active_ch % Active channel index
.ch_name % Active channel name
.ch_name0 % All channel name
.ad_factor % AD multiplicative factor to convert MEG data to [T]
pick1(ch,:) % position and direction of detection coils
on DICOM cord. [m],[normal unit vector]
pick2(ch,:) % position and direction of compensation coils
on DICOM cord. [m],[normal unit vector]
bexp( Nchannel, Tsample, Nrepeat) % measured fields [T]
New ver :2005-12-22 M. Sato
Copyright (C) 2011, ATR All Rights Reserved.
License : New BSD License(see VBMEG_LICENSE.txt)0001 function [meg_info,pick1,pick2,bexp]=readSBI_meg(meg_dir,meg_id,param) 0002 % --- Input 0003 % meg_dir : MEG data dir 0004 % meg_id : MEG system ID 0005 % --- Optional Input 0006 % param.time_win = [Tstart Tend]: [ms] 0007 % param.trials = trial index to extract 0008 % param.Pos_chk : if 1, pick are converted to DICOM cordinate. 0009 % 0010 % --- Output: 0011 % meg_info : structure with following field 0012 % .nch, % number of active gardiometers 0013 % .nch0 % number of gardiometers 0014 % .nsamp, % sampling number of measurement 0015 % .nprsamp, % sampling number for pre-trigger 0016 % .sampf, % sampling frequency 0017 % .nrept, % repeat number 0018 % .active_ch % Active channel index 0019 % .ch_name % Active channel name 0020 % .ch_name0 % All channel name 0021 % .ad_factor % AD multiplicative factor to convert MEG data to [T] 0022 % 0023 % pick1(ch,:) % position and direction of detection coils 0024 % on DICOM cord. [m],[normal unit vector] 0025 % pick2(ch,:) % position and direction of compensation coils 0026 % on DICOM cord. [m],[normal unit vector] 0027 % bexp( Nchannel, Tsample, Nrepeat) % measured fields [T] 0028 % New ver :2005-12-22 M. Sato 0029 % 0030 % Copyright (C) 2011, ATR All Rights Reserved. 0031 % License : New BSD License(see VBMEG_LICENSE.txt) 0032 0033 0034 if ~exist('param','var'), param = []; end; 0035 0036 % 0037 % Read header info 0038 % 0039 [meg_info, pick1, pick2] = read_sbi_meg_header(meg_dir, meg_id); 0040 0041 ix_ch = meg_info.active_ch ;% Active channel index 0042 amp = meg_info.ad_factor ;% AD factor to convert MEG data to [T] 0043 0044 % 0045 % Read MEG data 0046 % 0047 bexp = read_sbi_meg_data(meg_dir, meg_id, meg_info, param); 0048 0049 % 0050 % Select active channel & AD conversion 0051 % 0052 nch = length(ix_ch); 0053 bexp = bexp(ix_ch,:,:); 0054 0055 for i=1:nch, 0056 bexp(i,:,:) = bexp(i,:,:) * amp(i); 0057 end 0058 0059 if isfield(param,'Pos_chk') & param.Pos_chk == OFF, return; end; 0060 0061 % 0062 % Convert coil position to MRI-space 0063 % 0064 [pick1, pick2, meg_info] = ... 0065 trans_coord_sbi(meg_dir, meg_id, pick1, pick2, meg_info); 0066