Surveying, Mapping and GIS

I was just in a conversation with a friend of mine - I found that he's been wrestling with some homebrew code for managing large aerial photos - and the usual issues of performance, memory management, caching, and multiresolution data came up. A number of useful resources in the Open Source community are available in that arena, and I thought I would share some of them:

OSSIM - Open Source Software Image Map

http://www.ossim.org/

From the OSSIM site:

OSSIM is a high performance software system for remote sensing, image processing, geographical information systems and photogrammetry. It is an open source software project maintained at http://www.ossim.org/ and has been under active development since 1996. The lead developers for the project have years of experience in commercial and government remote sensing systems and applications.

OSSIM has been funded by several US government agencies in the intelligence and defense community and the technology is currently deployed in research and operational sites. The name OSSIM is a contrived acronym (Open Source Software Image Map) that is pronounced “awesome” – the acronym was established by our first government customer.

Another interesting effort ongoing is the Open Aerial Map project, spearheaded by the prodigiously prolific MetaCarta map ninja and OpenLayers/TileCache developer Christopher Schmidt:

OAM - Open Aerial Map

http://openaerialmap.org/

From the OAM site:

This project is an attempt to gather data from various free and open aerial imagery datasources around the world, and use them to create a single, coherent open world view.

If you are interested in seeing your data here, please email crschmidt@crschmidt.net.

Both of these sites contain code repositories, documentation, and other community resources are available, such as IRC chat channels.

I was amazed to see the articles in the news about the border fence debacle, where construction evidently went full-tilt along the US-Mexico border to construct a fence to prevent illegal immigration, following 120-year-old barbed wire strands, and without any apparent proper surveying research, and construction stakeout.

Evidently there are legal monuments spaced along the border, tall metal or concrete markers managed by the International Boundary and Water Commission, jointly operated by the US and Mexican government, but in constructing the fence, they evidently failed to do their due dilligence, and in fact the fence was revealed to be encroaching into Mexican territory. Certainly historic fence lines can have some meaning and significance as boundary evidence and as lines of possession in certain circumstances, but in this circumstance, particularly where an international boundary is concerned, I am frankly disturbed that proper survey work went by the wayside.

I have to admit, I am a Google Earth junkie, and as a technocrat, I have multiple machines at my desk. When one is going to be sitting semi-idle or running background tasks for any period of time, I sometimes fire up Google Earth on it, zoom in to a low altitude, put a slight angle tilt on the view, and set it at a lazy drift over some semi-randomly selected countryside.

Periodically, I will stop and sit in amazement at some of the scenery. Ancient ruins, meteor craters, breathtaking landscapes... the lunar landscape of the Libyan desert, you name it. I also periodically check out the goodies that sites like Google Earth Hacks have, as well as some of the other sites that track not just Google Earth, but other sites featuring imagery.

Google Karten tracks Google Maps, and picked up one of the more amazing things I've seen in a while... A cruise missile, captured in-flight over Utah...