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Comment by nobbis | Hacker News Reader

Another great free alternative is COLMAP (https://demuc.de/colmap).

And for those interested in doing this on mobile in real-time, we've just released a beta SDK (https://abound.dev) that lets you add real-time photogrammetry to any iOS app.

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And MicMac https://micmac.ensg.eu/index.php/Accueil

And OpenSFM https://github.com/mapillary/OpenSfM

I wish they better documented their specific benefits and short comings.

I find COLMAP has better dense depth maps, a more configurable pipeline, is cross-platform, the code is solid, and the accompanying research is principled (it takes a Bayesian approach to stereo matching.)

What aspects of these make them great alternatives in your opinion?

I wish I knew! They are all on my list to try, that's all for now. :)

Got it. If you’re just listing open source photogrammetry software, there are many more you can add, e.g. Regard3D, OpenMVG.

Considering this is a thread about open source software I feel like your self promotion of a proprietary service is out of place.

They also offered a link to a free library prior to doing so. I think the comment walks a fair line between substantive (in an area of which they clearly have domain knowledge) and advertisement.

Open source does not mean anti-commercial to most people.

I never said that.

It's a thread about photogrammetry.

> Meshroom: Open-Source Photogrammetry Software

Very cool stuff! Since you're using volumetric integration/fixed voxel size, one trick to get significantly improved visual texturing quality is to low-pass/smooth the mesh right before texturing.

Yes, we support Laplacian filtering of the level set prior to meshing in the SDK (plus other mesh smoothing techniques.) There are trade-offs involved.

How do COLMAP, Meshroom and VisualSFM compare to one another?

Some stuff that comes into mind:

* COLMAP and Meshroom are able to create a mesh from the pointcloud whereas VisualSFM is not. If you wish to create a mesh out of VisualSFM end result, you could use OpenMVS[1]

* COLMAP does not create a texture file for the resulting mesh - instead it uses vertex color for "texturing"

* COLMAP and Meshroom licenses permit commercial usage - VisualSFM does not (you need to license it)

From these three I've found that COLMAP works the best and VisualSFM comes second. Meshroom has a nice feature that allows you to add images into your model incrementally (I think without complete recompute) but it didn't work that well yet.

What comes to open source photogrammetry in general, my opinion is that COLMAP + OpenMVS or OpenMVG[2] + OpenMVS are the tools to go albeit the command line interface with huge amount of possible options can be a bit tricky at first.

1. https://github.com/cdcseacave/openMVS

2. https://github.com/openMVG/openMVG

Thanks for this overview.

> Meshroom has a nice feature that allows you to add images into your model incrementally

VisualSFM also does not recompute when adding photos later, IIRC what I read in the manual.

Is it possible to use the Apple Face ID sensor to perform a kinect-like 3D mapping of an environment or is the range of those sensors too limited for that?

Range is too limited, it's front-facing (can't see what you're scanning), and the OS-provided SLAM system isn't available (so tracking error accumulates.) Issues that will disappear in the long-run, of course.

One startup taking that approach is https://standardcyborg.com. Apologies if linking to a business is unseemly - they are YC-backed at least.

Jeff from SC here. Thanks @nobbis!

This looks really cool. Is there a demo application published somewhere that I could use to test?

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