OpenCV with stereo 3D reconstruction

Question

Say I plan to use OpenCV for 3D reconstruction using a stereo approach...and I do not have any special stereo camera but only webcams.

1.)How do I build a cheap stereo s

Answer 1

Firstly, ensure that your web cams don't have any inbuilt autofocus technology. As the cameras should have fixed focal length.

1) Align the cameras in canonical configuration with varying baseline distance. Then calibrate them using opencv's stereo_calib.cpp program. Usually, the distance will be 20-60cms. For some web cameras even 10cm will give you better results. If rms error and reprojection error are less than 0.5 then you could consider that the stereo setup is ready.

2) Yes, it is possible to capture stereo images from the setup which I just mentioned. Check out this link for capturing images from cameras.

OpenCV provides better algorithms from which one can do wonders with 3D vision.

Stereo is better suited for indoor environment as it is very sensitive to lighting variations.