# How to convert a binary 3d matrix to mesh.

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MG Poirot on 29 Apr 2016
Commented: Md Nurul Karim on 19 Nov 2019
I have a 3D binary matrix with 1 being filled volume, and 0 being empty. For example I've added a representation of this matrix filled with a sphere but the matrix could also have been filled with irregular content.
I would like to construct a mesh from 3D binary matrix volume, how would I go about it?
I have come across the isosurf function, but I was not sure if it was applicable or how to get my data in the right format.
Thanks.

Mike Garrity on 29 Apr 2016
Yes, I would think that isosurface is the first thing to try. Just give it the 3D array and an isolevel of 1/2. It'll use linear interpolation to put a surface down the middle of where the 1's and 0's meet.
[x,y,z] = ndgrid(-1:.05:1);
v = sqrt(x.^2+y.^2+z.^2) < .5;
isosurface(v,1/2)
As you can see, the result can be a little lumpy.
If you want your mesh to follow the grid without any interpolation, then you'll probably want a different approach.
Xander May on 5 Jun 2017
Karima, it would seem your 3D object does not have a 'Surface' anywhere besides what you are seeing. The ISOSURFACE function creates a mesh of the surface of an object, but because your object only has a surface where the interior walls of the canyon are, with other thigns extending out of the view window, that is the only part ISOSURFACE is able to render

Noor Aamer on 4 May 2018
How can I get a 3D binary image from 2D binary image?
Md Nurul Karim on 19 Nov 2019
Just stack the 2D binary images on top of each other and make a 3D binary matrix.
then you can watch it in Volume viewer app.
You can also extract surface out of it.