Page MenuHomec4science
Files F122578168

openedf.m
No OneTemporary
Actions

File Metadata

Created
Sun, Jul 20, 16:59

openedf.m
View Options

function [DAT,H1]=openedf(FILENAME)
% EDF=openedf(FILENAME)
% Opens an EDF File (European Data Format for Biosignals) in MATLAB (R)
% <A HREF="http://www.medfac.leidenuniv.nl/neurology/knf/kemp/edf.htm">About EDF</A>
% Copyright (C) 1997-1998 by Alois Schloegl
% a.schloegl@ieee.org
% Ver 2.20 18.Aug.1998
% Ver 2.21 10.Oct.1998
% Ver 2.30 5.Nov.1998
%
% For use under Octave define the following function
% function s=upper(s); s=toupper(s); end;
% V2.12 Warning for missing Header information
% V2.20 EDF.AS.* changed
% V2.30 EDF.T0 made Y2K compatible until Year 2090
% This program 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.
%
% This program 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 for more details.
%
% You should have received a copy of the GNU General Public License
% along with this program; if not, write to the Free Software
% Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
SLASH='/'; % defines Seperator for Subdirectories
BSLASH=char(92);
cname=computer;
if cname(1:2)=='PC' SLASH=BSLASH; end;
fid=fopen(FILENAME,'r','ieee-le');
if fid<0
fprintf(2,['Error LOADEDF: File ' FILENAME ' not found\n']);
return;
end;
EDF.FILE.FID=fid;
EDF.FILE.OPEN = 1;
EDF.FileName = FILENAME;
PPos=min([max(find(FILENAME=='.')) length(FILENAME)+1]);
SPos=max([0 find((FILENAME=='/') | (FILENAME==BSLASH))]);
EDF.FILE.Ext = FILENAME(PPos+1:length(FILENAME));
EDF.FILE.Name = FILENAME(SPos+1:PPos-1);
if SPos==0
EDF.FILE.Path = pwd;
else
EDF.FILE.Path = FILENAME(1:SPos-1);
end;
EDF.FileName = [EDF.FILE.Path SLASH EDF.FILE.Name '.' EDF.FILE.Ext];
H1=char(fread(EDF.FILE.FID,256,'char')'); %
EDF.VERSION=H1(1:8); % 8 Byte Versionsnummer
%if 0 fprintf(2,'LOADEDF: WARNING Version EDF Format %i',ver); end;
EDF.PID = deblank(H1(9:88)); % 80 Byte local patient identification
EDF.RID = deblank(H1(89:168)); % 80 Byte local recording identification
%EDF.H.StartDate = H1(169:176); % 8 Byte
%EDF.H.StartTime = H1(177:184); % 8 Byte
EDF.T0=[str2num(H1(168+[7 8])) str2num(H1(168+[4 5])) str2num(H1(168+[1 2])) str2num(H1(168+[9 10])) str2num(H1(168+[12 13])) str2num(H1(168+[15 16])) ];
% Y2K compatibility until year 2090
if EDF.VERSION(1)=='0'
if EDF.T0(1) < 91
EDF.T0(1)=2000+EDF.T0(1);
else
EDF.T0(1)=1900+EDF.T0(1);
end;
else ;
% in a future version, this is hopefully not needed
end;
EDF.HeadLen = str2num(H1(185:192)); % 8 Byte Length of Header
% reserved = H1(193:236); % 44 Byte
EDF.NRec = str2num(H1(237:244)); % 8 Byte # of data records
EDF.Dur = str2num(H1(245:252)); % 8 Byte # duration of data record in sec
EDF.NS = str2num(H1(253:256)); % 8 Byte # of signals
EDF.Label = char(fread(EDF.FILE.FID,[16,EDF.NS],'char')');
EDF.Transducer = char(fread(EDF.FILE.FID,[80,EDF.NS],'char')');
EDF.PhysDim = char(fread(EDF.FILE.FID,[8,EDF.NS],'char')');
EDF.PhysMin= str2num(char(fread(EDF.FILE.FID,[8,EDF.NS],'char')'));
EDF.PhysMax= str2num(char(fread(EDF.FILE.FID,[8,EDF.NS],'char')'));
EDF.DigMin = str2num(char(fread(EDF.FILE.FID,[8,EDF.NS],'char')')); %
EDF.DigMax = str2num(char(fread(EDF.FILE.FID,[8,EDF.NS],'char')')); %
% check validity of DigMin and DigMax
if (length(EDF.DigMin) ~= EDF.NS)
fprintf(2,'Warning OPENEDF: Failing Digital Minimum\n');
EDF.DigMin = -(2^15)*ones(EDF.NS,1);
end
if (length(EDF.DigMax) ~= EDF.NS)
fprintf(2,'Warning OPENEDF: Failing Digital Maximum\n');
EDF.DigMax = (2^15-1)*ones(EDF.NS,1);
end
if (any(EDF.DigMin >= EDF.DigMax))
fprintf(2,'Warning OPENEDF: Digital Minimum larger than Maximum\n');
end
% check validity of PhysMin and PhysMax
if (length(EDF.PhysMin) ~= EDF.NS)
fprintf(2,'Warning OPENEDF: Failing Physical Minimum\n');
EDF.PhysMin = EDF.DigMin;
end
if (length(EDF.PhysMax) ~= EDF.NS)
fprintf(2,'Warning OPENEDF: Failing Physical Maximum\n');
EDF.PhysMax = EDF.DigMax;
end
if (any(EDF.PhysMin >= EDF.PhysMax))
fprintf(2,'Warning OPENEDF: Physical Minimum larger than Maximum\n');
EDF.PhysMin = EDF.DigMin;
EDF.PhysMax = EDF.DigMax;
end
EDF.PreFilt= char(fread(EDF.FILE.FID,[80,EDF.NS],'char')'); %
tmp = fread(EDF.FILE.FID,[8,EDF.NS],'char')'; % samples per data record
EDF.SPR = str2num(char(tmp)); % samples per data record
fseek(EDF.FILE.FID,32*EDF.NS,0);
EDF.Cal = (EDF.PhysMax-EDF.PhysMin)./ ...
(EDF.DigMax-EDF.DigMin);
EDF.Off = EDF.PhysMin - EDF.Cal .* EDF.DigMin;
tmp = find(EDF.Cal < 0);
EDF.Cal(tmp) = ones(size(tmp));
EDF.Off(tmp) = zeros(size(tmp));
EDF.Calib=[EDF.Off';(diag(EDF.Cal))];
%EDF.Calib=sparse(diag([1; EDF.Cal]));
%EDF.Calib(1,2:EDF.NS+1)=EDF.Off';
EDF.SampleRate = EDF.SPR / EDF.Dur;
EDF.FILE.POS = ftell(EDF.FILE.FID);
if EDF.NRec == -1 % unknown record size, determine correct NRec
fseek(EDF.FILE.FID, 0, 'eof');
endpos = ftell(EDF.FILE.FID);
EDF.NRec = floor((endpos - EDF.FILE.POS) / (sum(EDF.SPR) * 2));
fseek(EDF.FILE.FID, EDF.FILE.POS, 'bof');
H1(237:244)=sprintf('%-8i',EDF.NRec); % write number of records
end;
EDF.Chan_Select=(EDF.SPR==max(EDF.SPR));
for k=1:EDF.NS
if EDF.Chan_Select(k)
EDF.ChanTyp(k)='N';
else
EDF.ChanTyp(k)=' ';
end;
if findstr(upper(EDF.Label(k,:)),'ECG')
EDF.ChanTyp(k)='C';
elseif findstr(upper(EDF.Label(k,:)),'EKG')
EDF.ChanTyp(k)='C';
elseif findstr(upper(EDF.Label(k,:)),'EEG')
EDF.ChanTyp(k)='E';
elseif findstr(upper(EDF.Label(k,:)),'EOG')
EDF.ChanTyp(k)='O';
elseif findstr(upper(EDF.Label(k,:)),'EMG')
EDF.ChanTyp(k)='M';
end;
end;
EDF.AS.spb = sum(EDF.SPR); % Samples per Block
bi=[0;cumsum(EDF.SPR)];
idx=[];idx2=[];
for k=1:EDF.NS,
idx2=[idx2, (k-1)*max(EDF.SPR)+(1:EDF.SPR(k))];
end;
maxspr=max(EDF.SPR);
idx3=zeros(EDF.NS*maxspr,1);
for k=1:EDF.NS, idx3(maxspr*(k-1)+(1:maxspr))=bi(k)+ceil((1:maxspr)'/maxspr*EDF.SPR(k));end;
%EDF.AS.bi=bi;
EDF.AS.IDX2=idx2;
%EDF.AS.IDX3=idx3;
DAT.Head=EDF;
DAT.MX.ReRef=1;
%DAT.MX=feval('loadxcm',EDF);
return;

Event Timeline

c4science · Help