Architectural Example

[James]

Hi there,

I don't often (ever?) post results of my work due to the hassle of getting permission to do so, but since this is just a 'by-product' of the actual deliverable, which was simply high resolution 2D orthophotos, i think i can get away with it...

https://sketchfab.com/models/4f8344edaabe47a1bd5ca3e4cb5821ac

James

[r0xx]

Looks awesome! Will you share how (Quadrocopter, Helicopter, Other drone?) you made the model? And how did you get a result that detailed? How many images were used for this? What settings in PhotoScan?

[James]

Thanks!

We took a hybrid approach using ground based terrestrial laser scanning from ground level and some at roof level, in conjunction with photoscan.

Photos of the facade were taken by a person in a boom lift with a nikon d800, and the bell tower was reached by someone dangling from a crane in a basket - not me!

For the main wings of the elevation we only used the laser scan data for the surface reconstruction.

For the bell tower and portico where the laser scan data was patchy we combined it with the dense cloud from photoscan, literally just copying and pasting one pointcloud into the other.

Surface reconstruction was done in an external application, and imported into photoscan for texturing.

We took 1,343 images in total. About 500 around the bell tower, 250 on the portico, and 300 on each wing.

Photoscan data was registered to the laser scan data using 95 ground control points, total error around 15mm.

[r0xx]

Thanks alot for the interesting background story! Good work on that one!

[stihl]

Interesting results. Thanks for sharing!!

[sastun1962]

really good! thanks

[igor73]

That is the best building scan i have seen so far.  Fantastic job.  What was the application of doing the?  What will the model be used for? 

[James]

Thanks!

The end product (2D orthophotos) were required as a historical record, a tool for condition assessment and for marking up results from other surveys.

This elevation was processed in separate chunks, and I only merged them into a single textured 3D model to show that the possibility existed.

[igor73]

Where you able to merge all the sides of the building?  Did you use Agisoft for merging?  Awesome work! 

[James]

We used 3DReshaper for creating the 4 meshes (2x wings, portico and bell tower), and to merge them together to make this model.

Immediately after merging the 4 chunks in 3dreshpare I split them back into 4 chunks again! That meant that the seams would align perfectly and i could just weld duplicate vertices to reassemble them to a single mesh after texturing. I was careful to put the seams in corners where they would not be too visible as there would be no blending of the textures at these seams.

I brought the 4 meshes into the respective 4 chunks (wings, portico and bell tower) in photoscan to texture and then used blender to recombine into a single object.

The photogrammetric survey was only on this main elevation, although laser scan data was collected all round the building.