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I have a single photo of a cylindrical object from an unfortunate point of view with an image printed on its side. Are there any utils or plugins to unwrap the texture of the cylinder in the photo into a plane (a flat UV map)? Or how to do that manually?

I was thinking it would need some way to use a grid with curved baselines, to manually set it on the pattern, and then map the pattern from curved grid to rectangular one with straight lines and equal distribution between them.

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I'd go with 3d (I use Blender but it would be +/- the same in any software) but just because I don't know a better solution. Let's say I have an image like this and I want to extract this CAHABA thing (a random image from Internet)

enter image description here

I'd setup a scene so that camera matches photo as much as possible. Here I had to eyeball a camera orientation, if there was a boxy shape in the photo I could've used as a reference, I'd use a camera matching software/plugin (like an opensource fSpy) to restore perspective more precisely.

enter image description here

Then I'd project UVs from the camera — this object will be source for remapping:

enter image description here

Then I'll make a duplicate of the object: this duplicate will have a proper aligned UVs and will be a target for remapping:

enter image description here

enter image description here

Then baking. There're different ways of doing that, I'll use a free EasyBake addon. Baking process is transferring different data from one object to another (mostly), in this case I'm transfering color information from Source to Target:

enter image description here

Here's the result:

enter image description here

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  • Nice work! I will have to try out fSpy, that's a nice tool.
    – JohnB
    Jan 22 '20 at 18:43
  • @JohnB yes, it's great and easy to use. It has made my life much easier :} Jan 22 '20 at 18:59
  • Ok, this is a good method if you have a good set of wanishing lines. But if not then its kindof painful to do this.
    – joojaa
    Jan 24 '20 at 15:20
  • Well, if there are no any points of references to restore a camera any method will be painful, no? But life is pain in general, so whatevs Jan 24 '20 at 15:36
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Yes there are tools for this. Given what i know today this is what i would do:

  1. Put object on a table. Do a 3D photo survey, multiple images from multiple different distances and direction.
  2. Bring it to a photogrametry software (like say meshroom).
  3. Bring it to a 3D app (like say blender) and do a cylindrical render. Or bake uv map to uv map, or mesh to mesh.

Simply because this is the least painless and most general of all the methods. General meaning if you know this you can apply it to a sphere, building or a statue of a [insert culturally relevant icon here].

This might seem like overkill to you. But the other methods are really painful when you screw them up (not really an if). This method has losely coupled dependencies so you can easily redo each step separately and but even better you can adapt to things you learned later that you should have accounted for.

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  • thanx, very interesting, but my issue is different, not doing 2D texture form a lot of photos to render 3D, I have a singe photo (2D photo of cylindrical object) with unforunate point of view and need to get a part of its UV-map plained
    – AndreyBark
    Jan 22 '20 at 7:49

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