3D Modelling of buildings

Video and Photo Editing
21

I’ve been using WebODm for surface mapping mainly … I’m certainly interested in what settings you use for the full 3D re-constructions as my previous attempts at buildings have been disappointing :frowning:

Tangentally, Open Drone Mapper have introduced a rolling shutter correction algorithm. However you need to have an accurate number for the sensor readout time.

Anyone know what this is for the Mini 2 … or have access to an arduino/raspberry pi to do the measurement? (GitHub - OpenDroneMap/RSCalibration: Docs and scripts to estimate a camera's rolling shutter readout time)

22

Hi ximi,

I typically use the default 3D Model setting, with the only changes being enabling neighbour match to save time, and upping the max vertices to 300,000. I don’t necessarily stop the drone to take the photos. Making sure the overlap is good is the key factor.

I am not using the rolling shutter correction, as like you say there aren’t a lot of values out there at the moment, but I have the kit to do the measurement so will do mine for the mini 3 soon. I can spare the arduino for a week or two so if you are in the UK and were willing to post it back (will be a large letter I’d guess) I can ship the test rig to you so you could test yours as well?

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23

I too have been playing with orthophotography and 3D modelling - with my Spark and Air 2S. I use WebODM and am mightily impressed - plus Meshlab and Sketchfab.

My first missions were flown manually but I am now starting to use Maven to plan flights. You can also use the free Arducopter Mission Planner to draw polygons and grids. Then download the mission as a CSV file for import into Litchi or Maven. This tool is needed for conversion into CSV: Convert Mission Planner (ArduCopter) Waypoint Surveys

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24

The pics I want to upload to Grey Arrows are JPEG. I cannot find the “add photo” button on this website.

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15GlanRoof-007
15GlanRoof-0073175×2375 1.87 MB

Thanks, finally found the “upload” button.
This is the kind of bread-and-butter stuff we do as building surveyors. a typical roof to a detached house.

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So - just a normal jpeg - not a 3D image at all.

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Same icon, albeit a different position than mobile

image

Or just drag-and-drop using a computer.

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We did proper 3D images of several buildings, see one attached. We used a Mini 3 and a lot of clever photogrammetry with Agisoft software.
Bentinck Mansions-3D model

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That’s a 2D screenshot of your 3D software. It’s not a “3D image”.

See the above for posting proper 3D images.

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:man_facepalming:

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Yes that’s obvious. Do you know what the file size would be if I tried downloading it in full 3D? About a trillion Mb. Plus it cost my client a small fortune and I don’t think they would like it exhibited in the round for all and sundry… It is only meant to be a representation of what we can do, apart from just taking jpegs.

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Not quite

See post 6

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Also known as … about 125 gigabytes.

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All the size is the textures, the raw output is pretty large (2.5GB for one of those), and a lot of people may find themselves over the 100mb limit for sketch fab but you can just shrink the image files for the obj file in the photo editing application of your choice and they’ll get reprojected onto the mesh correctly automatically

I normally go for 1/4 or 1/8 resolution on the meshes to get them to fit on sketch fab

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