| % Y=GaussFilt2d(X,sigma,pixdim) | |
| % Gaussian blurring. Pixel dimension is considered (1mm isotropic by default) | |
| % pixdim and sigma can be a vector of length 1 (if isotropic) or 2 (anisotropic) | |
| function Y=GaussFilt2d(X,sigma,pixdim) | |
| if exist('pixdim','var')==0 | |
| pixdim=[1 1]; | |
| end | |
| if numel(pixdim)==1 | |
| pixdim=pixdim*ones(1,2); | |
| end | |
| if numel(sigma)==1 | |
| sigma=sigma*ones(1,2); | |
| end | |
| sigma=sigma./pixdim; % in voxels | |
| w=ceil(2.5*sigma); | |
| Y=X; | |
| if sigma(1)>0, v=-w(1):w(1); g=exp(-0.5*v.*v/(sigma(1)*sigma(1))); g=g/sum(g); Y=imfilter(Y,reshape(g,[length(v) 1]),'replicate'); end | |
| if sigma(2)>0, v=-w(2):w(2); g=exp(-0.5*v.*v/(sigma(2)*sigma(2))); g=g/sum(g); Y=imfilter(Y,reshape(g,[1 length(v)]),'replicate'); end | |