What is the baseline of a stereo camera?

Question

Could someone here explain what exactly is the baseline of a camera?

Theriault

Answer 1

You're apparently dealing with stereo, where the baseline is (at least normally) the distance between the two lenses.

Senseless

Thanks yes I am dealing with stereo.Given the Focal length of the system and baseline+disparity values do you know a formula to calculate the x,y,z? – Theriault

@Manish: Not off the top of my head, no. This seems like something OpenCV would already have though. – Senseless

Yeah we tried opencv 's stereorectify and it didnt seem to work ....throws up some error which is why I was wondering if I could do it alternatively by doing the math. – Theriault

@Manish: That probably deserves to be asked as a question of its own. – Senseless

Answer 2

I believe

Z (depth) = (focalLength * baseline) / disparity

Other coordinates can be found here: http://www.ptgrey.com/support/kb/index.asp?a=4&q=63&ST=

Corrincorrina

I know this topic is old, but given this formula, what disparity do I use if I have a list of disparities, such as for all pixels? And will knowing the pixel size help me determine the baseline in this scenario? – Purple

Answer 3

The baseline (distance between both cameras) will influence the depth range that you can observe with a stereo camera, and also your depth resolution. The same also applies to the focal length of the lenses that you use.

Assuming that you process a disparity range with a constant size, then the following rules apply:

• Increasing the baseline will increase your depth resolution, but will also increase the minimum distance to the camera
• Increasing the focal length will also increase the depth resolution and minimum distance to the camera, but also reduce the field of view.

This relationship can be studied with the following online calculator: https://nerian.com/support/resources/calculator/

Jawbone

Answer 4

Baseline is the distance between 2 stereo camera. When you do stereo Calibration, the openCV method return R, T (rotation and translation between your cameras)

Reinhold

I believe you meant, two camera lenses in a stereo camera. making it a bit clearer would be a good idea. – Lafrance