colmap VS OpenMVG (open Multiple View Geometry)

Not saying its easy to use, but there is an application gui and it is free: https://github.com/colmap/colmap

Colmap (Model folders (BIN and TXT), dense workspaces, NVM, PLY)

See colmap for example https://colmap.github.io/

You're looking into a problem called photogrammetry, and a well-studied one at that. I'd recommend looking into "shape from motion" (sfm); specifically techniques that do "dense reconstruction." I'd recommend COLMAP to start with. It does pose estimation from images (e.g. you point it at a bunch of images and it will figure out the relative poses of the cameras that took them), as well as sparse and dense reconstcution.

COLMAP builds dense meshes from a collection of cameras https://colmap.github.io/

I’ve seen references to using COLMAP (https://colmap.github.io/) to estimate camera position/pose, e.g. here

Classical photogrammetry, where I agree with u/tdgros that the way to go is https://colmap.github.io/. There are actually better variants in literature but nothing is more reliable and user-friendly than COLMAP. This will give you a very precise point cloud, that can be meshed if needed.

Try to find a community that will know more about openMVG, like the discussion tab on their github.

OpenMVG (JSON, NVM, PLY)

I find openMVG very decent, FTXUI might be a good one and nlohmann's json library is also pretty nice. I don't really know of any project that strictly adheres to the core guidelines, except maybe for some of Jason Turner's (sample) projects.

I am looking for some pointers to papers/open-source software that can do fast and accurate depth estimation from multi-view videos. I am aware of colmap and OpenMVG software but was curious to know if there are others out there that outperform these. I am also interested in any state-of-the-art for depth estimation using unsupervised or self-supervised neural networks.

OpenMVG is super cool, and the project lead Pierre is very generous with his time.

Meshroom is just a Python wrapper for VSfM. OpenMVS seems like the package most customizers are starting to use. https://github.com/openMVG/openMVG