Load surface data created by FreeSurfer and 'mris_convert' (.asc file). Vertex number is reduced. Inverse talairach transformation is applied. --- Syntax function [V,F] = vb_fs_load_surface(ascfile,xfmfile,reduce_ratio) --- Input ascfile: include cortical structure created by FreeSurfer reduce_ratio: Reduction ratio of vertex number (0-1) xfmfile: Linear transformation file (Talairach transformation) - This program supports linear transformation only (.xfm). --- History 2005-08-24 Taku Yoshioka 2008-10-16 Taku Yoshioka Input variable 'xfmfile' can be empty. Copyright (C) 2011, ATR All Rights Reserved. License : New BSD License(see VBMEG_LICENSE.txt)
0001 function [V,F] = vb_fs_load_surface(ascfile,xfmfile,reduce_ratio) 0002 % Load surface data created by FreeSurfer and 'mris_convert' 0003 % (.asc file). Vertex number is reduced. Inverse talairach 0004 % transformation is applied. 0005 % 0006 % --- Syntax 0007 % function [V,F] = vb_fs_load_surface(ascfile,xfmfile,reduce_ratio) 0008 % 0009 % --- Input 0010 % ascfile: include cortical structure created by FreeSurfer 0011 % reduce_ratio: Reduction ratio of vertex number (0-1) 0012 % xfmfile: Linear transformation file (Talairach transformation) 0013 % 0014 % - This program supports linear transformation only (.xfm). 0015 % 0016 % --- History 0017 % 2005-08-24 Taku Yoshioka 0018 % 2008-10-16 Taku Yoshioka 0019 % Input variable 'xfmfile' can be empty. 0020 % 0021 % Copyright (C) 2011, ATR All Rights Reserved. 0022 % License : New BSD License(see VBMEG_LICENSE.txt) 0023 0024 % Load surface data 0025 [F0,V0] = load_surface(ascfile); % inner function 0026 0027 % Vertex reduction 0028 if nargin>=3 & reduce_ratio<1, 0029 [F,V] = reducepatch(F0,V0,reduce_ratio); 0030 else 0031 F = F0; V = V0; 0032 end 0033 0034 if nargin>=2 & ~isempty(xfmfile), 0035 % Load .xfm file 0036 xfm = load_xfm(xfmfile); 0037 0038 % Inverse transformation 0039 xfm_inv = inv(xfm); 0040 Vext = [V'; ones(1,size(V,1))]; 0041 V = (xfm_inv*Vext)'; 0042 V = V(:,1:3); 0043 end 0044 0045 %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%% 0046 % 0047 % Inner functions 0048 % 0049 function [F,V] = load_surface(ascfile) 0050 0051 % Open file 0052 fid = fopen(ascfile,'r'); 0053 fgetl(fid); % comment line 0054 tmp = fscanf(fid,'%d %d',2); % # of vertices and patches 0055 NV = tmp(1); 0056 NF = tmp(2); 0057 tmp = fscanf(fid,'%e %e %e %e',inf); 0058 V = reshape(tmp(1:NV*4),[4 NV])'; 0059 F = reshape(tmp(NV*4+1:end),[4 NF])'; 0060 V = V(:,1:3); 0061 F = F(:,1:3)+1; 0062 0063 fclose(fid); 0064 0065 function xfm = load_xfm(xfmfile) 0066 0067 % Open file 0068 fid = fopen(xfmfile,'r'); 0069 0070 % Search line starts with 'Linear_Transform' 0071 chk = 0; 0072 while chk==0, 0073 str = fgetl(fid); 0074 if strcmp(str,'Linear_Transform ='), chk = 1; end; 0075 end 0076 0077 % Read three lines (transformation matrix) 0078 xfm = zeros(4,4); 0079 for i=1:3, xfm(i,:) = str2num(fgetl(fid)); end; 0080 xfm(4,:) = [0 0 0 1]; 0081 0082 fclose(fid); 0083