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Show HN: I 3D scanned the interior of the Great Pyramid at Giza (giza.mused.org)

1752 points by lukehollis ↗ HN
Hey HN, I 3d scanned the interior of the Great Pyramid / Khufu's pyramid for the Giza Project this summer and just finished the guided version to share. Would love feedback and/or problems you encounter.

I used both a Leica BLK 360 and Matterport Pro 2 to do the scanning and the Matterport SDK for the web viewer. Matterport's web display with Three.js has been the most accessible to a wide audience in the past (previous iterations are in Unity and Unreal, but difficult to download over slower connections).

I've been interviewing social studies teachers around the 6th grade level to create teaching materials as well, and these along with other monuments that I've scanned at Giza are up at https://giza.mused.org/

Cheers from Cairo--and thanks for any feedback.

290 comments

[ 2.5 ms ] story [ 269 ms ] thread
petargyurov
That is insanely cool.

The dollhouse view is nice. It would be great if you could see a 2D schematic of where you are in the pyramid as you're exploring.

Incredible job!

citrons
Actually liked that it lacked a minimap. Got a better sense of scale. After going trough most of the tunnels and getting stuck and kings chamber there, couldn't crawl back, I zomemed out and was shocked by the scale of the tunnels.
lukehollis
Thanks to you both for feedback on the minimap--this is one that we've had some requests for but I haven't started on yet.
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JohnJamesRambo
Oh wow, thank you for doing this. I’ll probably never be able to go to the real thing and this has been a fascination since childhood! I’ve got every part memorized from a book I had that had line drawings of the chambers.
massinstall
I’m curious to see it but FYI it doesn’t work on an iPhone with Firefox (you can never get past the first screen).
elliotpo
i am using it on an iPhone with Firefox right now
hatsubishi
Is it possible to see it in VR?
seydor
Works great with Quest2 , and it s amazing
Bad_CRC
with the normal browser?
seydor
Yes

Matterport always worked well for me. Surprisingly i have found that some other startups in the VR real estate space do not work at all with the Quest. It's very odd to build a product that doesnt work with the (by far) most popular headset

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sneak
What is the reason that Mixpanel and GTM are on this page? Is there a specific reason that such invasive tracking is required for an educational resource that does not generate revenue?
mikebonnell
They likely use some of the metrics to continue to get grant funding. You gave us $1m in grant money which we used to produce this webpage which has XXX millions of views. I'm sure other tools would suffice but given it's a project at Harvard, they may have institutional requirements.
easytiger
Incredible. Going through this gave me similar sentiments to when i first used my school library copy of Encarta 98.

Question: there are some blurred out areas, how come?

e.g. https://imgur.com/a/6Ca5EYG

mkl
I think it's just that the scanner doesn't look straight up.
jackcarter
Camera limitation – it doesn't capture a full sphere. That's exactly the spot where I also noticed it.
nimrody
Beautiful! Thanks for doing this work.

Can you explain a bit on the process that was used to create this? How do you determine your position inside the pyramid precisely?

(would make for a great dungeon-style game :)

joshvm
I've used the BLK 360 before so some comment here. Essentially you scan at various points within the volume of interest, e.g. you walk around, place the scanner, scan, repeat. Each scan takes a few minutes at high angular resolution. Leica provides software called Register (or Cyclone) to match the scans together. Because you generally don't have GPS (the BLK doesn't have a GPS onboar and GPS is anyway much more inaccurate than the scan resolution - metres versus millimetres), the software has to do some kind of feature matching to stitch the scans. You get "links" between adjacent scanning points, and then you do a big optimisation pass to combine the scans.

This scan matching is by far the most difficult and time consuming bit. Probably OP had to manually align the scans as a first pass and then the software takes over using some algorithm like ICP (iterative closest point).

This is still only "internal" (i.e. scans are correct relative to each other, but you don't know where the full scan is) and you'd have to combine with an external reference point to geo-locate in the world. Doesn't really matter for this because you're just viewing the pyramid on its own, and you're not overlaying on a map. If you were, then usually what you have to do is take several ground control point (GCP) that are known with high accuracy and then reference that in the scan. You could geo-reference these using an RTK GPS or something, but it's quite difficult to get world coordinates at the millimetre scale and it rarely matters if you're that precise as long as the scan itself is consistent.

This video from Leica shows the full workflow for a typical use case (scanning a house with indoor and outdoor points). Note the point where they link inside and outside, around 16 mins in https://www.youtube.com/watch?v=AV0LPKowOXU

bambax
Complete newbie here, but wouldn't it be possible to affix some marks on the walls to help with the stitching afterwards?
0_____0
When working with LIDAR scanning systems (Total systems etc) that generate a point cloud, this is exactly what you'd do. Affix a target or fiducial (a pattern you can apply to a surface that shows up in the scan, either because it's very reflective or because it has a high contrast pattern on it), and use those as reference points to stitch your clouds together.
MezzoDelCammin
yeah, this is how things used to be done maybe 10y ago. Spheres (good for 360 symmetry) or checkerboard stickers. Problem is, nobody will probably allow You to put stickers onto the interior of the Great Pyramid.

These days there's a shift towards automatic "stitching" (scan registration) on an accompanying device (tablet or a laptop).

Here's a demo of Trimble X7 (about 3y old product). Full disclosure - I worked on part of this. Not sure how much I can go in detail, but the video shows a pretty good basic demo of how this works:

https://www.youtube.com/watch?v=PApO60lOhlg&ab_channel=Surve...

loufe
Awesome, thanks for sharing. We use cyclone for 3D CMS scans of open holes at the mine I work at. Cool to see other use cases. Were you using 3DReshaper before the rebranding?
lukehollis
Thanks for visiting! I'll put together a blog post, but it was similar to the process in my previous work here: https://blog.mused.org/digitizing-luxor-temple-a-virtual-fie...

Similar except I captured with Matterport Capture and then downloaded and aligned data captured with BLK after in Cyclone so that we'd have both sets.

mattfrommars
I had spent few weekends in my attempt to automate the process of generating 3D model from pictures. The underlying issue and concern folks have with matterport is their lock in. You are free to upload images to it but not allowed to self host or use their resource to generate the 3D dollhouse.

The regular way requires to feed the photo into multiple layer of software. Example, generate a point cloud, create a mesh from it, clean up the mesh and port it a Fanwood to be consumed (unity. Unreal, etc) this is all manual.

I am genuinely curious how the folks at matterport are able to do it with next to no human input after feeding it 2d pictures.

terhechte
This is really really cool! I enjoyed the explanations as well as the fantastic images
ryanmarr
Where are the puzzles that open the door to the linking book?
layer8
The page crashes for me on iOS.
malteof
Same! iPhone 12 on latest iOS.
ErneX
Try tapping the “aA” on the URL bar and disable content blockers.
layer8
Doesn’t help.
[dead] zach_garwood
alex_suzuki
What’s with the passive-aggressive unhelpful Apple-hating comments?

Just users of a browser with 20% of mobile market share, reporting a bug.

And btw, I can confirm this crashes for me some way into the pyramid (iOS 16).

moffkalast
That is so odd, after all Safari is known to have wide support for everything. /s
robmerki
This is absolutely amazing work. I have been searching for something exactly like this for quite some time. I am beyond thrilled that this now exists. THANK YOU.
lukehollis
Thanks for visiting! There are a few of these scans in the works that I linked in the comments if they're interesting for Ancient Egypt or elsewhere.
spaceman_2020
Same feelings. I've been fascinated by ancient Egypt as long as I can remember and this is just about perfect.
ErneX
Crashes on my iPhone 13 Pro running latest iOS version / Safari.

Update: turning off content blockers solves the crashing issue.

sdo72
This is very amazing. Thank you very much!
runjake
As many others have commented. My first thought was "Amazing!"

The only thing I encountered is that my mouse wheel scrolling was a bit too touchy and I kept accidentally zooming too much into a 3D scene while scrolling the text.

But that doesn't really matter, because this is amazingly cool.

green-eclipse
This is amazing! Incredible work! Thank you for doing this project.

FYI I found a typo - the word "cuts":

> It's 750 by 750 feet at the base and is made of over 2 million large, limestone blocks cuts from the surrounding area.

Also - from one of the angles shown, it looks like there's a golf course next to the pyramids? Not at all what I expected!

groffee
There's a pizza hut across the road as well lol
lukehollis
Thanks! And haha yes, definitely visit Giza someday--it's an incredible place to work.
mkl
This is great!

I noticed a few apostrophes missing in the captions in "King's Chamber" and "Queen's Chamber".

lukehollis
Thanks for visiting&feedback--will get this fixed!
kodah
This was a really cool experience. Thanks for putting this together.
_joel
Awesome work! I've been in there and one of the things missing is the change it humidity and temperature that hits you, maybe on the next revision ;)
lukehollis
Uff too real. I worked up a sweat on this one
neoneye2
Well made. Amazing to explore. Much appreciated.

Tested in my Firefox 106.0.1 on macOS Monterey 12.6, and it works great.

cush
Aaaaand the site crashes in ios safari
timbit42
That doesn't mean there is a problem with the website.
cryptozeus
I an sure its good, doesn’t work on safari on ios 16
zach_garwood
That sounds like an Apple problem. Works perfectly on Firefox on Android, not to mention Chromium on Linux.
soared
Incredible! I was under the impression there were tons of passages and chambers that were intricate, thank you for teaching me otherwise!
tmilard
It's nice. Maybe the best matterport's example I have seen so far... The 3D in the transitions [of two 360 photos] are really good and the pixel quality is great.

But still... The very limited part of Matterport is that it is "mostly" a series of 360 photos.

Now, because a pyramid is mainly a long corridor, you do not see too much those limitations.

So great.

Thierry, developper of https://free-visit.net/

arnaudsm
It's not only 2D 360, there's full 3D photogrammetry. Click on the dollhouse button on the bottom left.
lukehollis
I hear you--I think this is limitation is useful for bandwidth/loading time constraints.