Multi-Camera Calibration Algorithm Implemented by Caliscope

[crocis]

I would like to learn the algorithm implemented by Caliscope for multi-camera calibration. Where can I find this information?

[mprib]

Aside from digging through the code, the basic overview is:

1. get intrinsic parameters for each camera (focal lengths/center + lens distortion).
2. Initialize parameters for the bundle adjustment process

• relies on intrinsic parameter estimates
• perform simultaneous stereocalibration between each pair of cameras
• construct a complete camera array by anchoring to a single camera reference frame and chaining cameras to it based on quality of stereo calibration

4. Perform the actual bundle adjustment using the initialized parameters.

I realize that may not be a terribly satisfying overview, but that's the flow from 10,000 feet. If you want to get a clearer handle on things, I'd recommend learning specifically about bundle adjustment (Cyrill Strachniss on youtube has some great videos). There isn't anything terribly novel happening here, I'd argue that the value of Caliscope is that it implements the information processing pipeline in an efficient and robust way that quickly converges. Compared with alternative open source packages that perform multicamera calibration, it also uses more intrinsic camera parameters which allows for a more accurate estimate.