Changing stereo vision baseline via software

Question

I'm trying to estimate the distance with stereo system of far objects. I have rectified the images acquired after calibration process and I have built the disparity map.

Is it now possible to change the baseline (and the maximum depth achievable) through changing the stereo calibration parameters; for example vector T or image center Cx contained in camera matrix?

Answer 1

Given that your hardware is unchanged, you cannot change any parameters related to that. So the baseline and camera matrices are fixed. Baseline, lens parameters and pixel size together determine the maximal depth resolution you can achieve.

You might be able to slightly improve your result through superresolution techniques or some other trick, but this will not dramatically improve your results. Especially for faraway objects.

Answer 2

No, it is not possible.

By considering pinhole camera model and epipolar geometry:

• WCS World Coordinate System
• R Rotation of a Camera in WCS
• C Camera Position in WCS
• I Identity Matrix
• K Camera Matrix
• P Projection Matrix
• B Baseline

Projection Matrix P = K R [I -C]

After stereo rectification:

The images have to be within the same plane (Coplaner images), and all the epipolar lines are parallel. Also, epipoles are at infinity.

What changes? What does not change?

• R and K change for each camera.
• B and C do not change.
• P changes for each camera as well (P depends on R and K).
• Both cameras get the same K and R.
• P is different for each camera (C is different (Baseline))