Often times, I am able to get a perfect track using external tools and scripts etc... however; I am never able to use these tracks for the reason that I can never figure out how to orient the floor correctly. it is always off.
What I mean by this; is that while all my methods seem to orient the camera appropriately- up is up, down is down, etc- I can never figure out the exact positioning of the ground plane/wall plane/etc. the blender grid always has a parallax offset from the footage's perceived motion.
for example; if I have footage of walking down a hallway- I can't seem to align blender's grid floor to be at the exact same height as the floor perceived in the footage; which makes VFX stuff impossible to get looking right, despite the actual motion being solved near-perfectly.
another scenario is when I've tracked a camera using footage from a side-scrolling video game, and I have the exact same difficulty aligning the grid with the game's background plane (because despite the camera's perfect motion tracking, I can't figure out the precise parallax by eye.)
one way I attempt to align it in either scenario is to move to a random frame, move the camera up or down to match the grid up, then move to a different frame and move it again, etc...this doesn't always work and when it works, works poorly.
so what I am asking is; is there a way to align the blender floor grid with the footage's floor/wall/etc. when I've already tracked the camera and everything? if so, what might that be?
I bet there's a mathematic equation or something around that can determine the point of where something is based on the camera motion and the parallax, but I just don't know what.
I am willing to literally do my own math or write my own script if I really need to, but a script or plugin would be nice to know about if one already exists.