vb_readbdf

 vb_readbdf() -  Loads selected Records of an EDF or BDF File (European Data Format 
              for Biosignals) into MATLAB
 Usage: 
          >> [DAT,signal] = readedf(EDF_Struct,Records,Mode);
 Notes:
       Records - List of Records for Loading
       Mode    -       0       Default
                       1       No AutoCalib
                       2       Concatenated (channels with lower sampling rate 
                                             if more than 1 record is loaded)
 Output:
       DAT    - EDF data structure
       signal - output signal

 Author: Alois Schloegl, 03.02.1998, updated T.S. Lorig Sept 6, 2002 for BDF read

 See also: vb_openbdf(), sdfopen(), sdfread(), eeglab()

0001 % vb_readbdf() -  Loads selected Records of an EDF or BDF File (European Data Format
0002 %              for Biosignals) into MATLAB
0003 % Usage:
0004 %          >> [DAT,signal] = readedf(EDF_Struct,Records,Mode);
0005 % Notes:
0006 %       Records - List of Records for Loading
0007 %       Mode    -       0       Default
0008 %                       1       No AutoCalib
0009 %                       2       Concatenated (channels with lower sampling rate
0010 %                                             if more than 1 record is loaded)
0011 % Output:
0012 %       DAT    - EDF data structure
0013 %       signal - output signal
0014 %
0015 % Author: Alois Schloegl, 03.02.1998, updated T.S. Lorig Sept 6, 2002 for BDF read
0016 %
0017 % See also: vb_openbdf(), sdfopen(), sdfread(), eeglab()
0018 
0019 %    Version 2.11
0020 %    03.02.1998
0021 %    Copyright (c) 1997,98 by Alois Schloegl
0022 %    a.schloegl@ieee.org
0023                       
0024 % This program is free software; you can redistribute it and/or
0025 % modify it under the terms of the GNU General Public License
0026 % as published by the Free Software Foundation; either version 2
0027 % of the  License, or (at your option) any later version.
0028 %
0029 % This program is distributed in the hope that it will be useful,
0030 % but WITHOUT ANY WARRANTY; without even the implied warranty of
0031 % MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
0032 % GNU General Public License for more details.
0033 %
0034 % You should have received a copy of the GNU General Public License
0035 % along with this program; if not, write to the Free Software
0036 % Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA  02111-1307, USA.
0037 %
0038 %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
0039 % This program has been modified from the original version for .EDF files
0040 % The modifications are to the number of bytes read on line 53 (from 2 to
0041 % 3) and to the type of data read - line 54 (from int16 to bit24). Finally the name
0042 % was changed from readedf to vb_readbdf
0043 % T.S. Lorig Sept 6, 2002
0044 %
0045 % Header modified for eeglab() compatibility - Arnaud Delorme 12/02
0046 %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
0047 
0048 function [DAT,S]=vb_readbdf(DAT,Records,Mode)
0049 if nargin<3 Mode=0; end;
0050  
0051 EDF=DAT.Head; 
0052 RecLen=max(EDF.SPR);
0053 
0054 S=NaN*zeros(RecLen,EDF.NS);
0055 DAT.Record=zeros(length(Records)*RecLen,EDF.NS);
0056 DAT.Valid=uint8(zeros(1,length(Records)*RecLen));
0057 DAT.Idx=Records(:)';
0058         
0059 for nrec=1:length(Records),
0060 
0061     NREC=(DAT.Idx(nrec)-1);
0062     if NREC<0 fprintf(2,'Warning READEDF: invalid Record Number %i \n',NREC);end;
0063 
0064     fseek(EDF.FILE.FID,(EDF.HeadLen+NREC*EDF.AS.spb*3),'bof');
0065     [s, count]=fread(EDF.FILE.FID,EDF.AS.spb,'bit24');
0066 
0067     try, 
0068         S(EDF.AS.IDX2)=s;
0069     catch,
0070         error('File is incomplete (try reading begining of file)');
0071     end;
0072 
0073     %%%%% Test on  Over- (Under-) Flow
0074 %    V=sum([(S'==EDF.DigMax(:,ones(RecLen,1))) + (S'==EDF.DigMin(:,ones(RecLen,1)))])==0;
0075     V=sum([(S(:,EDF.Chan_Select)'>=EDF.DigMax(EDF.Chan_Select,ones(RecLen,1))) + ...
0076            (S(:,EDF.Chan_Select)'<=EDF.DigMin(EDF.Chan_Select,ones(RecLen,1)))])==0;
0077     EDF.ERROR.DigMinMax_Warning(find(sum([(S'>EDF.DigMax(:,ones(RecLen,1))) + (S'<EDF.DigMin(:,ones(RecLen,1)))]')>0))=1;
0078     %    invalid=[invalid; find(V==0)+l*k];
0079                              
0080     if floor(Mode/2)==1
0081         for k=1:EDF.NS,
0082             DAT.Record(nrec*EDF.SPR(k)+(1-EDF.SPR(k):0),k)=S(1:EDF.SPR(k),k);
0083         end;
0084     else
0085         DAT.Record(nrec*RecLen+(1-RecLen:0),:)=S;
0086     end;
0087 
0088     DAT.Valid(nrec*RecLen+(1-RecLen:0))=V;
0089 end;
0090 if rem(Mode,2)==0    % Autocalib
0091     DAT.Record=[ones(RecLen*length(Records),1) DAT.Record]*EDF.Calib;
0092 end;                   
0093 
0094 DAT.Record=DAT.Record';
0095 return;         
0096