projective geometry: how do I turn a projection of a rectangle in 3D into a 2D view

Posted by bonomo on Programmers See other posts from Programmers or by bonomo
Published on 2012-11-10T18:11:17Z Indexed on 2012/11/10 23:16 UTC
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3d

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geometry

So the problem is that I have a 3D projection of a rectangle that I want to turn into 2D. That is I have a photo of a sheet of paper laying on a table which I want to transform into a 2D view of that sheet. So what I need is to get an undistorted 2D image by reverting all the 3D/projection transformations and getting a plain view of the sheet from the top. I happened to find some directions on the subject but they don't suggest an immediate instruction on how this can be achieved. It would be really helpful to get a step-by-step instruction of what needs to be done. Or, alternatively, a link on a resource that breaks it down to little details.

Thank you

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