[Feature request] StereoCamera model and OpenCV initializations

🚀 Feature

For Stereo Vision tasks it would be handy to have a StereoCamera model which can be initialized with two kornia.geometry.camera.PinholeCamera and the stereo calibration. The StereoCamera can have some handy methods such as StereoCamera.get_disparity_from_depth and StereoCamera.get_depth_from_disparity and other methods for working with disparity maps.

In addition to this, I propose a feature for both the PinholeCamera and proposed StereoCamera that would add a factory method to both, called something like from_OpenCV_calibration, such that we can easily initialize a PinholeCamera and StereoCamera from OpenCVs calibrateCamera and stereoCalibrate. OpenCVs calibration methods are the de facto standard in many stereo vision tasks.

Motivation

This will help researchers and developers who work on Stereo Vision tasks and want to use the nice features of Kornia otherwise. A lot of research is being put into Stereo Vision and Disparity Map estimation and I think Kornia will be a valuable tool here.

Additional context

I would be happy to contribute these proposed features.

[copaah]

@edgarriba I will! Looking into it this weekend and hopefully have a first draft.

[edgarriba]

@copaah join our slack https://join.slack.com/t/kornia/shared_invite/zt-csobk21g-CnydWe5fmvkcktIeRFGCEQ