There seems something wrong about depth calculation in cv::omnidir::stereoReconstruct function

I am confused about the implementation of absolute depth calculation in omnidir.cpp, which is different from the original paper (Binocular Spherical Stereo).

specifically, the depth is calculated as follows:

float depth = float(baseline * f /<float>(j, i));

but in the original paper (Binocular Spherical Stereo), the absolute depth is calculated as follows:
where \rho_r is the depth of left image.

By the way, another repository pdi which provides a solution to get the panorama depth image from a single fisheye stereo image pair, uses the above equation from original paper to calculate depth.

I am wondering if I am missing something? or are these two implementations equivalent?
or is it just a bug?

Looking forward to your reply !