Forensic Visualization with Complex Meshing

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vislaw
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Forensic Visualization with Complex Meshing

Post by vislaw »

I took on a new interesting forensic case this past weekend involving a crime scene in a large storage building in the Tenderloin district of San Francisco. The amount of junk inside the building was staggering:
INTERIOR.jpg
The critical events took place all along several "rabbit trails" winding through the piles of old furniture, appliances and lumbar and the client hired us to produce a 3D animation that will orient the jury as to the movements of the two principal characters throughout this space. The client wanted a scale top-down view as an exhibit that could be used during trial as well as a 3D fly-through to give the jury a sense of the space.

I did 38 scans using FARO 120S and X330 scanners. SCENE 6.2 put together the orthographic top view very nicely:
Top_Down_SM.jpg
For the 3D fly-through we always prefer converting our point clouds to a mesh whenever possible because it gives us better rendering performance as well as control over lighting and shadows. This was the most complex small-area scene I've ever generated a mesh for. I haven't worked with the new mesh generation tool in SCENE yet so I used Thinkbox SEQUOIA, which I've always appreciated for its meshing capabilities.
MESHING.jpg
MESH_RENDER.jpg
I flew a DJI Phantom 4 drone to acquire a photogrammetric model of the building exterior:

The incident in question took place four years ago when the building exterior had not been painted and while a small market occupied the corner space. I used Google Street View historical images to acquire textures to make the building exterior match the period in question:
Drone_Photogrammetry.jpg
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Re: Forensic Visualization with Complex Meshing

Post by vislaw »

kmcm
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Re: Forensic Visualization with Complex Meshing

Post by kmcm »

Great work Mark! (as always). That scene meshed together really nicely. I'm impressed you got so much detail from such a cluttered room!

Another crucial game for the Blackcaps tonight (NZ cricket team), no doubt you'll be watching...

Kurt
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Re: Forensic Visualization with Complex Meshing

Post by ddustin »

Excellent work Mark!

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Re: Forensic Visualization with Complex Meshing

Post by tbwester »

Amazing thanks for sharing.

A bit envious of the multitude of methods forensic folks get to use!
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Re: Forensic Visualization with Complex Meshing

Post by john-newbegin »

Wow, nice job.. good to see a very thorough project completed using the tools we have available. How satisfied with the final product that you gave the client were they? Just wondering if it turned out in the way that they were intending the data to prove and if they seemed grateful for your contribution.
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Re: Forensic Visualization with Complex Meshing

Post by gschofield »

Very nice Mark,
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Re: Forensic Visualization with Complex Meshing

Post by vislaw »

john-newbegin wrote:Wow, nice job.. good to see a very thorough project completed using the tools we have available. How satisfied with the final product that you gave the client were they? Just wondering if it turned out in the way that they were intending the data to prove and if they seemed grateful for your contribution.
Thanks, John. Actually the case goes to trial this week and we're still working out what the final exhibits will be. This started out as a last-minute request for an orthographic top-down view of the scene that could be used as a big 30" x 40" exhibit board. The client was very happy with the result and when I showed them that the scan could actually be viewed in 3D they commissioned the additional work.

I have been pursuing an informal campaign to educate our clients regarding the benefits of combining terrestrial scanning with drone-based photogrammetry. This is a good example of how the drone provides a large "macro" (albeit low-resolution) cloud that supplements and expands the high-resolution laser-scanning.
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Re: Forensic Visualization with Complex Meshing

Post by Scott »

Well done! : +1
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Re: Forensic Visualization with Complex Meshing

Post by vislaw »

kmcm wrote:Great work Mark! (as always). That scene meshed together really nicely. I'm impressed you got so much detail from such a cluttered room!

Another crucial game for the Blackcaps tonight (NZ cricket team), no doubt you'll be watching...

Kurt
I don't know what an "ODI" shirt is but I just placed a pre-order for a BLACKCAPS 2016/17 Men's Replica ODI Shirt so count me as a supporter now!
nzblackcaps.jpg
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