Location, location

[alfred]

http://www.blair.cfgn.net/alfreds/

My collection of DTED1 data is currently being uploaded to that location 
(its slowly dribbling out of my ADSL connection onto the server).

If this resource could be useful to others I can find a more permanent 
home for it. If you are missing a pane you need drop me a line and I 
will see if I can find it. Also, I have source code to load dted panes 
into memory (in a useful format) and code to stitch together panes so if 
you want it again drop me an email and I will see what I can provide 
(the code is written in vanilla C, compiles under linux (gcc 2.96) and 
win32 (msvc++ 6.0)).

Reynolds, Alfred wrote:

> DTED1 is a 3 sec arc which equates to about 90m on the ground. It is
> topographic only (it used to be/still is derived from people reading
> topographic maps and inputting the data). Buildings would certainly be a
> problem but I suspect that its only really an issue for those in heavily
> built up areas (which means its not a problem for people in Canberra ;).
> Fresnel zone clearance with buildings will be an issue, but as a rough guide
> it will be close enough. I do not know of a source of info that contains
> structures (dted1 is +/- 30m in the vertical....), if someone does I would
> love to know about it :)
> 
> As for the data itself, it comes in 1 degree wide chunks (with the filename
> denoting the sw corner of the data), with each file being about 2.76mb. I
> will upload the data to a webserver I have access to when I get home and
> then post a URL here. 
> 
> 
> 
> 
>>-----Original Message-----
>>From: David Leonard [mailto:david.leonard at itee.uq.edu.au]
>>Sent: Wednesday, October 17, 2001 1:23 PM
>>To: Reynolds, Alfred
>>Cc: wireless at lists.samba.org
>>Subject: RE: Location, location
>>
>>
>>On Wed, 17 Oct 2001, Reynolds, Alfred typed thusly:
>>
>>
>>>I can supply a reasonably complete set of digital terrain 
>>>
>>data for the
>>
>>>eastern sea board in DTED level 1 format (which is fine for 
>>>
>>radio line of
>>
>>>sight work). I also have the c code to load the data and 
>>>
>>produce height
>>
>>>profiles :) I may even be able to provide code to spit out 
>>>
>>path losses
>>
>>>between two points (I need to double check copyright on that).
>>>
>>>What I don't have lots of is time :)
>>>The data is about 500mb worth, if someone is interested I 
>>>
>>will look into
>>
>>>making up a web frontend to the data and algorithms (right 
>>>
>>now I have a java
>>
>>>based app).
>>>
>>David Arnold just alerted me to this thread...  Mmmm, DTED level 1...
>>
>>The AUSLIG DEM i got was 9 second res and has shown to be 
>>problematic in two
>>ways:
>>	- it's almost useless for people nearby each other (ie 
>>within 1km)
>>	  since its so coarse
>>	- its data from a *surface model*.. ie buildings, trees, etc.
>>	  structures are removed and its just the ground level... so
>>	  it gives misleading plots in some cases.
>>
>>DTED 1 (www.fas.org/irp/program/core/dted.htm) is 3 second 
>>arc (~100m res)
>>and (although I'm not sure) it is also a surface model that 
>>ignores structures?
>>Can you confirm this?
>>
>>Alfred, it would be really nice if you could put up a HTTP 
>>interface that
>>allowed people to retreive raw segments of your data... of 
>>course perhaps
>>limited to say squares of size 1 minute of arc? :)
>>
>>I would certainly extend the brismesh mapping tools to make 
>>use of that! :)
>>
>>d
>>-- 
>>David Leonard                           David.Leonard at itee.uq.edu.au
>>Dept of Inf. Tech. and Elec. Engg   _   Ph:+61 404 844 850
>>The University of Queensland       |+|  
>>
> http://www.itee.uq.edu.au/~leonard/
> QLD 4072  AUSTRALIA               ~` '~
> B73CD65FBEF4C089B79A8EBADF1A932F13EA0FC8
> 
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> 


-- 
Alfred Reynolds
alfred at mazuma.net.au