How to find neighbor voxels of a given voxel?

Question

Sandhiya Prakash 2017-3-15

0
链接

此问题的直接链接

https://ww2.mathworks.cn/matlabcentral/answers/329918-how-to-find-neighbor-voxels-of-a-given-voxel

评论： Makis 2020-11-25

Hi! I am working with 3D MRI image of size(164x187x145). For a given voxel i need to consider 26 neighbouring 3x3x3 patch.(now 27 scalar values)Then consider all 26 neighbouring conventional 3x3x3 patches and compute average intensity for all these neighbouring patches.(So totally i have 53 scalar intensity values).How to perform this? Anyone who knows Plz reply !! code that i referred is as follows

function[IndexNeighbours] = findNeighbours(Index,MatrixSize)
 %%**************************************************************************
% Module name:      findNeighbours.m
% Version number:   1
% Revision number:  00
% Revision date:    10-2013

2013 (C) Copyright by Patrick Granton Maastro Clinic

%  Outputs:
%      IndexNeighbours = The index positions of valid voxels 
%  Usage: [IndexNeighbours] = findNeighbours(33014,[400 400 400])

Description:

%*************************************************************************
% References: 
%
%*************************************************************************
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%  %%*************************************************************************
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 -1 0 0];
[I J K] = ind2sub([MatrixSize],Index);
neighbours = Base+repmat([I J K],[26 1]);
valid_neighbours = (1 - sum(neighbours(1:26,:)<=0,2));
valid_neighbours_Indices = find(valid_neighbours==1);
IndexNeighbours = sub2ind([MatrixSize],[neighbours(valid_neighbours_Indices,1)],[neighbours(valid_neighbours_Indices,2)],[neighbours(valid_neighbours_Indices,3)]);
end