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View Full Version : Accurate 'Iso type' mapping



ravells
11-09-2009, 04:47 PM
The Ordinance Survery is testing out a new method of mapping using lasers (http://www.ordnancesurvey.co.uk/oswebsite/media/news/2009/october/futuremap.html). This is very, very cool.

Ascension
11-09-2009, 05:39 PM
That's all sorts of wicked cool.

Redrobes
11-09-2009, 09:01 PM
Just in case anyone missed the vid...

http://www.youtube.com/watch?v=jANDq2Ad5H4

Its just texture mapped laser scanning but they must be scanning from multiple directions and using some point cloud re-meshing to get the model back from it. Its all not that new but its very nicely done. Cambridge uni does a lot of this sort of stuff.

Now if you had this model as a starting point then that thing that Waldronate mentioned with the 3D twin digi camera thing would come into its own. You could upres the model significantly with that.

You will be seeing little sesna type planes with google written on the side soon...

töff
11-09-2009, 09:27 PM
"Trialling"? ... as in, if you are TRYING something, it's a TRIAL, which means you are (not trying but) TRIALLING?

God, I love language.

Yoda was right. There is no "try."

RobA
11-09-2009, 11:45 PM
The Ordinance Survery is testing out a new method of mapping using lasers (http://www.ordnancesurvey.co.uk/oswebsite/media/news/2009/october/futuremap.html). This is very, very cool.

More accurate than lidar contour mapping?

-Rob A>

waldronate
11-10-2009, 09:24 AM
Nothing new here except the scale of the activity and the total amount of coverage over the area of interest (possibly the availability as well).

It does look like the classic problem of reflective surfaces showed up in one area of a wall of windows. The image texture shows in the right place, but with the wrong information. The lidar data tends to get really nasty on reflective things and it takes lots of samples to smooth it out.

I wonder how long it took them to acquire this and if it was ground-based or air-based. Back in 2000 I interviewed with Cyra and they gave me a demo of their lidar mapping system. Just a few thousand points per second but with a pretty good range accuracy (it was a time of flight measurement device and they were getting a few picoseconds resolution or so). It didn't work past 100m or so. To scan a whole scene took an hour or so.

Stereo cameras work fairly well in most cases but are limited in their depth resolution for a single pair. Now when you start moving the camera with good position and pose data then you can get good results.