sread.m

matlab数字信号处理工具箱

                S = cumsum(S);
                HDR.mode8.accu = S(size(S,1),:);
                
        elseif HDR.VERSION == 80, 
                [S,count] = fread(HDR.FILE.FID, [HDR.NS,DataLen], 'uint8');  
                S = S'-128; DataLen = count/HDR.NS;
                
        elseif HDR.VERSION == 160, 
                [S,count] = fread(HDR.FILE.FID, [HDR.NS,DataLen], 'uint16');  
                S = S'-2^15; DataLen = count/HDR.NS;
                
        elseif HDR.VERSION == 16, 
                [S,count] = fread(HDR.FILE.FID, [HDR.NS,DataLen], 'int16'); 
                S = S'; DataLen = count/HDR.NS;
                
        elseif HDR.VERSION == 61, 
                [S,count] = fread(HDR.FILE.FID, [HDR.NS,DataLen], 'int16'); 
                S = S'; DataLen = count/HDR.NS;
                
        else
                fprintf(2, 'ERROR MIT-ECG: format %i not supported.\n',HDR.VERSION); 
                
        end;
        HDR.FILE.POS = HDR.FILE.POS + DataLen;   	
        S = S(:,HDR.InChanSelect);
        
        
elseif strcmp(HDR.TYPE,'TMS32'),
        tmp = NoS*HDR.SampleRate/HDR.SPR;
        if tmp~=round(tmp)	
                fprintf(2,'ERROR: NoS %f is not multiple of TMS32-blocksize %f. This is not supported yet.\n',NoS,HDR.SPR/HDR.SampleRate);
                return;
        end;
        NoBlks = min(tmp,HDR.NRec-HDR.FILE.POS);
        
        if nargin==3,
                tmp = StartPos*HDR.SampleRate/HDR.SPR;
                if tmp~=round(tmp)	
                        fprintf(2,'ERROR: StartPos %f is not multiple of TMS32-blocksize %f. This is not supported yet.\n',StartPos,HDR.SPR/HDR.SampleRate);
                        return;
                end;
                
                fseek(HDR.FILE.FID,HDR.HeadLen+StartPos*HDR.SampleRate/HDR.SPR*(HDR.AS.bpb+86),'bof');        
                HDR.FILE.POS = HDR.SampleRate/HDR.SPR*StartPos;
        end;
        
        S = [];
        for k = 1:NoBlks, 
                if all(HDR.GDFTYP==HDR.GDFTYP(1))
                        hdr = fread(HDR.FILE.FID,86,'char');
                        [s,c] = fread(HDR.FILE.FID,[HDR.NS,HDR.SPR],gdfdatatype(HDR.GDFTYP(1)));
                        S = [S;s'];
                        HDR.FILE.POS = HDR.FILE.POS + 1;
                else
                        hdr = fread(HDR.FILE.FID,86,'char');
                        s = zeros(HDR.SPR,HDR.NS);
                        for k1 = 1: HDR.SPR,
                                for k2 = 1: HDR.NS,
                                        [s(k1,k2),count] = fread(HDR.FILE.FID,1,gdfdatatype(HDR.GDFTYP(k2)));
                                end;
                        end;
                        S = [S;s'];
                        HDR.FILE.POS = HDR.FILE.POS + 1;
                end;
        end;
        S = S(:,HDR.InChanSelect);	
        
        
elseif strcmp(HDR.TYPE,'DEMG'),
        if nargin==3,
                fseek(HDR.FILE.FID,HDR.HeadLen+HDR.SampleRate*HDR.AS.bpb*StartPos,'bof');        
                HDR.FILE.POS = HDR.SampleRate*StartPos;
        end;
        [S,count] = fread(HDR.FILE.FID,[HDR.NS,HDR.SampleRate*NoS],gdfdatatype(HDR.GDFTYP));
        if count,
                S = S(HDR.InChanSelect,:)';
                HDR.FILE.POS = HDR.FILE.POS + count/HDR.NS;
        end;
        
        
elseif strcmp(HDR.TYPE,'ACQ'),
        if nargin==3,
                fseek(HDR.FILE.FID,HDR.HeadLen+HDR.SampleRate*HDR.AS.bpb*StartPos,'bof');        
                HDR.FILE.POS = HDR.SampleRate*StartPos;
        end;
        count = 0;
        if all(HDR.GDFTYP==HDR.GDFTYP(1)) & all(HDR.SPR==HDR.SPR(1))
                [S,count] = fread(HDR.FILE.FID,[HDR.NS,HDR.SampleRate*NoS],gdfdatatype(HDR.GDFTYP(1)));
        else
                fprintf(HDR.FILE.FID,'Warning SREAD (ACQ): interleaved format not supported (yet).');
        end;
        if count,
                S = S(HDR.InChanSelect,:)';
                HDR.FILE.POS = HDR.FILE.POS + count/HDR.AS.spb;
        end;

        
elseif strcmp(HDR.TYPE,'CFWB'),
        if nargin==3,
                fseek(HDR.FILE.FID,HDR.HeadLen+HDR.SampleRate*HDR.AS.bpb*StartPos,'bof');        
                HDR.FILE.POS = HDR.SampleRate*StartPos;
        end;
        [S,count] = fread(HDR.FILE.FID,[HDR.NS,HDR.SampleRate*NoS],gdfdatatype(HDR.GDFTYP));
        if count,
                S = S(HDR.InChanSelect,:)';
                HDR.FILE.POS = HDR.FILE.POS + count/HDR.NS;
        end;
        
        
elseif strcmp(HDR.TYPE,'AIF') | strcmp(HDR.TYPE,'SND') | strcmp(HDR.TYPE,'WAV'),
        if nargin==3,
                fseek(HDR.FILE.FID,HDR.HeadLen+HDR.SampleRate*HDR.AS.bpb*StartPos,'bof');        
                HDR.FILE.POS = HDR.SampleRate*StartPos;
        end;
        maxsamples = min(HDR.SPR,HDR.SampleRate*NoS)-HDR.FILE.POS;
        if maxsamples>0,
                [S,count] = fread(HDR.FILE.FID,[HDR.NS,maxsamples],gdfdatatype(HDR.GDFTYP));
        else
                S = []; count = 0;
        end;	
        S = S(HDR.InChanSelect,:)';
        HDR.FILE.POS = HDR.FILE.POS + count/HDR.NS;
        
        if ~HDR.FLAG.UCAL,
                if isfield(HDR.FILE,'TYPE')
                        if HDR.FILE.TYPE==1,
                                S = mu2lin(S);
                        end;
                end;
        end;
        
        
elseif strcmp(HDR.TYPE,'EGI'),
        if nargin==3,
                fseek(HDR.FILE.FID,HDR.HeadLen+HDR.AS.bpb*StartPos,'bof');        
                HDR.FILE.POS = HDR.SampleRate*StartPos;
        end;
        
        if HDR.FLAG.TRIGGERED,
                NoS = min(NoS,(HDR.NRec-HDR.FILE.POS));
                S = zeros(NoS*HDR.SPR,length(HDR.InChanSelect))+NaN;
                for i = (1:NoS),
                        SegmentCatIndex(HDR.FILE.POS+i) = fread(HDR.FILE.FID,1,'uint16');
                        SegmentStartTime(HDR.FILE.POS+i) = fread(HDR.FILE.FID,1,'uint32');
                        
                        [s,count] = fread(HDR.FILE.FID, [HDR.NS + HDR.EVENT.N, HDR.SPR], HDR.datatype);
                        tmp = (HDR.NS + HDR.EVENT.N) * HDR.SPR;
                        if count < tmp,
                                fprintf(HDR.FILE.stderr,'Warning SREAD EGI: only %i out of %i samples read\n',count,tmp);
                        end;
                        HDR.FILE.POS = HDR.FILE.POS + count/tmp;
                        
                        if (HDR.EVENT.N > 0),
                                [HDR.EVENT.POS,HDR.EVENT.CHN,HDR.EVENT.TYP] = find(s(HDR.NS+1:size(s,1),:)');
                                HDR.EVENT.N = length(HDR.EVENT.POS);
                        end 
                        S((i-1)*HDR.SPR + (1:size(s,2)),:) = s(HDR.InChanSelect,:)';
                end;
        else
                [S,count] = fread(HDR.FILE.FID,[HDR.NS + HDR.EVENT.N, HDR.SampleRate*NoS],HDR.datatype);
                tmp = (HDR.NS + HDR.EVENT.N) * HDR.SampleRate * NoS;
                if count < tmp,
                        fprintf(HDR.FILE.stderr,'Warning SREAD EGI: only %i out of %i samples read\n',count,tmp);
                end;
                HDR.FILE.POS = HDR.FILE.POS + round(count/(HDR.NS + HDR.EVENT.N));
                
                if (HDR.EVENT.N > 0),
                        [HDR.EVENT.POS,HDR.EVENT.CHN,HDR.EVENT.TYP] = find(S(HDR.NS+1:size(S,1),:)');
                        HDR.EVENT.N = length(HDR.EVENT.POS);
                end 
                S = S(HDR.InChanSelect,:)';
        end;
        
        
elseif strcmp(HDR.TYPE,'AVG'),
        S = repmat(nan,HDR.SPR,HDR.NS);
        count = 0;
        for i = 1:HDR.NS, 
                [tmp,c]     = fread(HDR.FILE.FID,5,'char'); % no longer used 
                count = count + c;
                [S(:,i), c] = fread(HDR.FILE.FID,HDR.SPR,'float');
                count = count + c*4;
        end
        S = S(:,HDR.InChanSelect);
        HDR.FILE.POS = HDR.FILE.POS + count/HDR.AS.bpb;
        
        
elseif strcmp(HDR.TYPE,'COH'),
        warning('.COH data not tested yet')
        if prod(size(NoS))==1 & nargin>2, 
                rows = NoS; cols = StartPos;
        elseif prod(size(NoS))==2
                rows = NoS(1); cols = NoS(2);
        else
                fprintf(HDR.FILE.stderr,'Error SREAD mode=COH: invalid arguments.\n');
        end;
        
        fseek(HDR.FILE.FID,HDR.COH.directory(rows,cols)+8,'bof'); % skip over a small unused header of 8 bytes 
        sr = fread(HDR.FILE.FID, HDR.SPR, 'float32');  % read real part of coherence    
        si = fread(HDR.FILE.FID, HDR.SPR, 'float32');  % read imag part of coherence    
        S = sr + i * si;
        
        
elseif strcmp(HDR.TYPE,'CSA'),
        warning('.CSA data not tested yet')
        S = fread(HDR.FILE.FID, [HDR.NRec*(HDR.SPR+6)*HDR.NS], 'float32');	        
        
        
elseif strcmp(HDR.TYPE,'EEG'),
        if nargin>2,
                fseek(HDR.FILE.FID,HDR.HeadLen+HDR.AS.bpb*StartPos,'bof');        
        end;
        
        NoS = min(NoS, HDR.NRec-HDR.FILE.POS);
        S   = zeros(NoS*HDR.SPR, length(HDR.InChanSelect));
        count = 0;
        for i = 1:NoS, %h.compsweeps,
                h.sweep(i).accept   = fread(HDR.FILE.FID,1,'uchar');
                tmp		    = fread(HDR.FILE.FID,2,'ushort');
                h.sweep(i).ttype    = tmp(1);
                h.sweep(i).correct  = tmp(2);
                h.sweep(i).rt       = fread(HDR.FILE.FID,1,'float32');
                tmp  		    = fread(HDR.FILE.FID,2,'ushort');
                h.sweep(i).response = tmp(1);
                h.sweep(i).reserved = tmp(2);
                
                [signal,c] = fread(HDR.FILE.FID, [HDR.NS,HDR.SPR], gdfdatatype(HDR.GDFTYP));
                
                S(i*HDR.SPR+(1-HDR.SPR:0),:) = signal(HDR.InChanSelect,:)';
                count = count + c;
        end;
        HDR.FILE.POS = HDR.FILE.POS + count/HDR.AS.spb;        
        
        
elseif strcmp(HDR.TYPE,'CNT'),
        if nargin>2,
                fseek(HDR.FILE.FID,HDR.HeadLen+HDR.SampleRate*HDR.NS*StartPos*2,'bof');        
                HDR.FILE.POS = HDR.SampleRate*StartPos;
        end;
        
        [S,count] = fread(HDR.FILE.FID, [HDR.NS, min(HDR.SampleRate*NoS, HDR.AS.endpos-HDR.FILE.POS)], 'int16');
        
        S = S(HDR.InChanSelect,:)';
        HDR.FILE.POS = HDR.FILE.POS + count/HDR.NS;
        
        
elseif strcmp(HDR.TYPE,'MFER'),
	if (HDR.FRAME.N ~= 1),
		fprintf(2,'Warning MWFOPEN: files with more than one frame not implemented, yet.\n');
		return;
	end
	
	N = 1;
	if ~isfield(HDR,'data'),
		fseek(HDR.FILE.FID,HDR.FRAME.POS(N),'bof');
		[tmp,count] = fread(HDR.FILE.FID,HDR.FRAME.sz(N,1:2),gdfdatatype(HDR.FRAME.TYP(N)));
        	if isnan(HDR.NRec),
        		HDR.NRec = count/(HDR.SPR*HDR.NS);
        	end;

        	if count==(HDR.SPR*HDR.NS), %% alternate mode format
        		tmp = reshape(tmp,[HDR.SPR,HDR.NS]);
        	else
        	        tmp = reshape(tmp,[HDR.SPR,HDR.NS,HDR.NRec]);   % convert into 3-Dim
        	        tmp = permute(tmp,[1,3,2]);                     % re-order dimensions
        	        tmp = reshape(tmp,[HDR.SPR*HDR.NRec,HDR.NS]);   % make 2-Dim 
        	end;
		HDR.data = tmp;
	end;

	if nargin>2,