Question

我有一个image.i想将此图像转换为graph.Pixels是节点，边缘代表8-neighborhood。我试过了

I=imread('cameraman.tif');
[r c]=size(I); 
%r = 32; c = 32;
%# Get the matrix size
diagVec1 = repmat([ones(c-1,1); 0],r,1);  %# Make the first diagonal vector
%#   (for horizontal connections)
diagVec1 = diagVec1(1:end-1);             %# Remove the last value
diagVec2 = [0; diagVec1(1:(c*(r-1)))];    %# Make the second diagonal vector
%#   (for anti-diagonal connections)
diagVec3 = ones(c*(r-1),1);               %# Make the third diagonal vector
%#   (for vertical connections)
diagVec4 = diagVec2(2:end-1);             %# Make the fourth diagonal vector
rc = r*c;
adj = spdiags([diagVec1;0],1,rc,rc);
adj = adj + spdiags([diagVec2; zeros(c-1,1)], c-1, rc,rc);
adj = adj + spdiags([diagVec3; zeros(c,1)], c, rc,rc);
adj = adj + spdiags([diagVec4; zeros(c+1,1)], c+1, rc,rc);
adj = adj + adj.';

%# plot adjacency matrix
subplot(121), spy(adj)

%# plot connected points on grid
[X Y] = meshgrid(1:c,1:r);
X = X(:); Y = Y(:);
[xx yy] = gplot(adj, [X Y]);
subplot(122), plot(xx, yy, 'ks-', 'MarkerFaceColor','r')
axis([0 r+1 0 c+1])
%# add labels
X = reshape(X',[],1) + 0.1; Y = reshape(Y',[],1) + 0.1;
text(X, Y(end:-1:1), cellstr(num2str((1:r*c)')) )

我尝试了这段代码。但内存不足问题;适用于32 * 32图像。不是重复的问题

Answer 1

您可以使用sparse_adj_matrix：一个实用程序函数，用于计算任意网格图的邻接矩阵（特别是2D 4连接或8连接）。
从github下载函数并输入

>> doc sparse_adj_matrix

了解如何使用它。

如何构建图像的连通分量图？

1 个答案: