Agisoft Metashape

Agisoft Metashape => General => Topic started by: AJ on January 13, 2015, 08:45:11 PM

Title: Car Scanning with Photogrammetry
Post by: AJ on January 13, 2015, 08:45:11 PM
Ten24 have, once again, appeared to have achieved the impossible and scanned a car with Photoscan.

http://www.ten24.info/?p=2019

I'm not sure if they'll come forward and say what they're doing to achieve such clean results from reflective/refractive surfaces, but does anyone hear have any ideas?

The only thing I can think of (which I have had some success with myself) is covering the whole object in talcum powder, but I'm not sure how feasible that would be with an entire car...
Title: Re: Car Scanning with Photogrammetry
Post by: chrisd on January 13, 2015, 09:10:46 PM
Developer spray (there are a few suppliers) seems to work pretty well. The talc sprays do not coat as evenly as the developer spray.
Title: Re: Car Scanning with Photogrammetry
Post by: mrb on January 14, 2015, 12:33:55 AM
I'd hardly say it's impossible.  I've "scanned" two cars before and got perfectly useable results.  You just have to use a polarizing filter and do it on a cloudy day.
Title: Re: Car Scanning with Photogrammetry
Post by: nadar on January 14, 2015, 12:20:24 PM
How do you get the original textures (colours, stickers, etc.)  is you cover the car with powder ?
I tried many option, including scanning a very dirt car, using polarizing filter, etc, but never get satisfying results, especially on windows and windscreen.
A possible solution should be to use fixed cameras rack (30-50 simultaneous cameras placed in a converging circular pattern) and shoot 2 versions of the same car, one "clean" and one "powered". Of course, the position of the cameras must be strictly the same.
Another solution is perhaps to use a turning table, but I did not find a solution to assure the positional stability of (relative) camera position
Title: Re: Car Scanning with Photogrammetry
Post by: FoodMan on January 14, 2015, 12:45:27 PM
look at the window texture... it was covered with Matt photo spray..  8)

http://www.ten24.info/ten24/wp-content/uploads/2015/01/CarScan01.jpg
Title: Re: Car Scanning with Photogrammetry
Post by: nadar on January 16, 2015, 11:34:14 AM
I think this is an image combining a 3D "solid mesh" (the back of the car) and a "textured" mesh (the front).
I'm really impressed by the quality of the mesh, especially on flat and reflective surfaces