matlab的segy输出

% WriteSegy : writes data to disk using SEGY REV 1 standard. % % EX % WriteSegy('datacube.segy',data,'dt',.004,'Inline3D',Inline,'Crossline3D',Crossline,'cdpX',X,'cdpY',Y); % % to use a specific SEG revision use : % WriteSegy('test.segy',seisdata,'revision',0); % SEG-Y Revision 0 % WriteSegy('test.segy',seisdata,'revision',1); % SEG-Y Revision 1 % % to use a specific Data Sampling Format use : % WriteSegy('test.segy',seisdata,'dsf',1); % IBM FLAOTING POINT % % Forice Revision 1 and IEEE Floating point : % WriteSegy('test.segy',seisdata,'dsf',5,'revision',1); % % See also : WriteSegyStructure, WriteSu, WriteSuStructure % % % (C) 2001-2004, Thomas Mejer Hansen, tmh@gfy.ku.dk/thomas@cultpenguin.com % % 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 % % Modifications made by Urs Boeniger allowing to add all possible headers % directly within this function. function WriteSegy(filename,data,varargin); if nargin<2; help WriteSegy; return; end [ns,ntraces]=size(data); if nargin>2 if length(varargin)>2; varargin=(reshape(varargin,2,(length(varargin)/2)))'; end fields=varargin(:,1); headers=cell2struct(varargin(:,2),fields,1); if isfield(headers,'dt')~=1 headers.dt=0.004.*1e+6; SegymatVerbose([mfilename,' - No dt set. Using dt=',num2str(headers.dt)],0) else headers.dt=headers.dt.*1e+6; end else headers.dt=.004.*1e+6; SegymatVerbose([mfilename,' - No dt set. Using dt=',num2str(headers.dt)],0) end %%%%%%%%%% % SET UP SegyHeader structure. if isfield(headers,'TextualFileHeader')==1, SegyHeader.TextualFileHeader=headers.TextualFileHeader;end if isfield(headers,'Job')==1, SegyHeader.Job=headers.Job;end; if isfield(headers,'Line')==1, SegyHeader.Line=headers.Line;end if isfield(headers,'Reel')==1, SegyHeader.Reel=headers.Reel;end if isfield(headers,'DataTracePerEnsemble')==1, SegyHeader.DataTracePerEnsemble=headers.DataTracePerEnsemble;end if isfield(headers,'AuxiliaryTracePerEnsemble')==1, SegyHeader.AuxiliaryTracePerEnsemble=headers.AuxiliaryTracePerEnsemble;end if isfield(headers,'dt')==1, SegyHeader.dt=headers.dt;end if isfield(headers,'dtOrig')==1, SegyHeader.dtOrig=headers.dtOrig;end if exist('ns')==1, SegyHeader.ns=ns; end if isfield(headers,'ns')==1, SegyHeader.ns=headers.ns;end if isfield(headers,'nsOrig')==1, SegyHeader.nsOrig=headers.nsOrig;end if isfield(headers,'EnsembleFold')==1, SegyHeader.EnsembleFold=headers.EnsembleFold;end if isfield(headers,'TraceSorting')==1, SegyHeader.TraceSorting=headers.TraceSorting;end if isfield(headers,'VerticalSumCode')==1, SegyHeader.VerticalSumCode=headers.VerticalSumCode;end %%%%%%%%%% %% CHOOSE WHICH SEGY REVISION AND DATATYPE TO USE %% DEFAULT IS REVISION 1, 4-byte IEEE % IF A SPECFIC REVISION HAS BEEN CHOSEN, USE THAT if isfield(headers,'revision')==1, if headers.revision==1, SegyHeader.SegyFormatRevisionNumber=100; else SegyHeader.SegyFormatRevisionNumber=0; end SegymatVerbose([mfilename,' : Using user specified SEG Y revision : ',num2str(headers.revision)],1) end % IF A SPECFIC DATA SAMPLING FORMAT HAS BEEN SELECTED USE THAT if isfield(headers,'dsf')==1, SegyHeader.DataSampleFormat=dsf; SegymatVerbose([mfilename,' : Using user specified Data Sample Format : ',num2str(revision)],1) end % UNCOMMENT THE FOLLOWING TWO LINES TO USE REVISION 1 (2002) %SegyHeader.SegyFormatRevisionNumber=100; % 2002 SEG Y STYLE %SegyHeader.DataSampleFormat=2; % '1'->4-byte IBM floating point % '2'->4-byte two's complement integer % '3'->2-byte two's complement integer % '5'->4-byte IEEE floating point (default) % '8'->1-byte two's complement integer % UNCOMMENT THE FOLLOWING TWO LINES TO USE REVISION 0 (1975) %SegyHeader.SegyFormatRevisionNumber=0; % 1975 SEoG Y STYLE %SegyHeader.DataSampleFormat=1; % '1'->4-byte IBM Floating Point % OPEN SEGY FILE HANDLE segyid = fopen(filename,'w','b'); % ALL DISK FILES ARE IN BIG % ENDIAN FORMAT, ACCORDING SEG % Y rev 1 % Write segy header SegyHeader=PutSegyHeader(segyid,SegyHeader); % Separate between single and multivalued header entries fnames=fieldnames(headers); fsize=zeros(size(fnames)); for k=1:length(fnames) fsize(k)=eval(['length(',['headers.',cell2mat(fnames(k))],')']); end mvals=1:length(fnames); svals=find(fsize==1);mvals(svals)=[]; for i=1:ntraces; SegyTraceHeader=headers; if (i/100)==round(i/100), SegymatVerbose(['writing trace ',num2str(i),' of ',num2str(ntraces)],0); end % Initialize SegyTraceHeader structure if isfield(headers,'headers')==0; SegyTraceHeader=InitSegyTraceHeader(ns,0.004.*1e+6); end if isfield(headers,'TraceNumber')==0 SegyTraceHeader.TraceNumber=i; SegyTraceHeader.TraceSequenceFile=i; end % ADD additional header entries % Write single valued trace headers into SegyTraceHeaders struct if isempty(svals)~=1; for t=1:length(svals); evalc(['SegyTraceHeader.',cell2mat(fnames(svals(t))),'= headers.',cell2mat(fnames(svals(t)))]); end end % Write multi valued trace headers into SegyTraceHeaders struct running % over the indices i. if isempty(mvals)~=1; for tt=1:length(mvals); evalc(['SegyTraceHeader.',cell2mat(fnames(mvals(tt))),'= headers.',cell2mat(fnames(mvals(tt))),'(',num2str(i),')']); end end PutSegyTrace(segyid,data(:,i),SegyTraceHeader,SegyHeader); end % CLOSE SEGY FILE HANDLE fclose(segyid);