How to create a graph of pixels?

I have this Matlab code that gives me in output this image in which I have a graph that sorrounds the obtacles. My idea now is to apply something like a Dijkstra algorithm to that graph or the shortestpath function of Matlab but I do not know how to create a graph of the pixels in white in the solution. Could anyone help me? Thanks

clc; clear all; close all;

img = imread('mappa3.png');
new_img = rgb2gray(img);
Icomplement = imcomplement(new_img);

BW = imbinarize(Icomplement);
out = bwskel(BW,'MinBranchLength',1e6);
imshow(out)

Answer 1

[Image Analyst]

That looks like the skiz. Search the help for skiz and you'll find a demo. Also look at these

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