How to restore 2d object from 3d world

File: projective transform.jpg (46KB, 643x218px) Image search: [Google]

46KB, 643x218px

>>7795891
>3. calculate rotation, translation, scale

These (+ shearing) are just affine transformations. You need a projective transformation.

>5. read the data lying between id points

I hope you're using bicubic/bilinear interpolation and not nearest neighbor.

Many thanks!

Think I'll get away without interpolation. I don't expect big angles and app is meant only to read binary sequences basing on areas' average brightness, so single pixels shouldn't be crucial. Still a very valueable nice!

> and not nearest neighbor.

What do you mean by that?

notice*

File: perspectivetransformations.jpg (413KB, 1280x926px) Image search: [Google]

413KB, 1280x926px

I needed to do something like that in a job. Its actually pretty easy if you know the the transformed and original points.

I used a python module:
http://scikit-image.org/docs/dev/api/skimage.transform.html#skimage.transform.ProjectiveTransform

But heres how you implement it from grounds up:
http://stackoverflow.com/questions/14177744/how-does-perspective-transformation-work-in-pil

Qt has functions to do the same

>>7796108
Nearest neighbor interpolation doesn't produce a nice image.

Look up image registration techniques, namely affine, non rigid, interpolation and similarly metrics