5
$\begingroup$

I have a question concerning the deformation of objects in photos. Which deformations can an object depicted on a photo undergo through viewpoint and condition changes?

Some deformations I have in mind are:

  • rotation
  • scale
  • shearing
  • translation
  • illumination
  • occlusion

Which deformations did I forget?

Best!

$\endgroup$
  • $\begingroup$ It there something like a paper discussing that? $\endgroup$ – jstr Apr 12 '12 at 17:29
  • $\begingroup$ Is shearing even possible in normal images of solid objects? $\endgroup$ – jstr Apr 12 '12 at 19:59
  • $\begingroup$ If you're panning a camera and it scans lines sequentially it could shear? $\endgroup$ – endolith Apr 12 '12 at 20:32
  • $\begingroup$ Ok but that's no usual scenario for taking pictures i guess $\endgroup$ – jstr Apr 13 '12 at 8:46
5
$\begingroup$

Since you have listed "illumination", I am assuming that "condition changes" include changes in lighting. So I would add cast shadows, which will change if you move the light source.

Also, all the geometric transformations you have listed are affine. But if you move the camera perspective changes as well. So you may want to consider the projective transformation.

$\endgroup$
  • $\begingroup$ yep forgot that one ;-) $\endgroup$ – jstr Apr 12 '12 at 19:46
1
$\begingroup$
  1. Noise, Filtering or any processing?

  2. Cropping

  3. Color conversions and brightness & contrast changes (inline with illumination but these are linear transformation).

  4. smearing.

  5. Flip or mirroring (not sure if this is possible)

  6. Gamma corrections, if related to devices?

Any thing you can do with GIMP or Photoshop?!

$\endgroup$

Your Answer

By clicking “Post Your Answer”, you agree to our terms of service, privacy policy and cookie policy

Not the answer you're looking for? Browse other questions tagged or ask your own question.