OpenStreetMap is an online effort to create a new map of the world that is completely free and free of restrictive copyright. One of the ways people create maps for it is by traveling around with a GPS tracking device and then drawing the roads using that data.

At this point OpenStreetMap does not have altitude data incorporated. On potential usage of altitude data would be to create a vertical profile of a bicycle route, or any other route.

I would like to create such an altitude profile based on the freely available NASA SRTM3 altitude data. Its horizontal resolution outside the United States is about 100 meters.

After a lot of discussion I have decided to keep the altitude data separate from the main data. Given a certain route, the altitude profile will be calculated on the fly.

My core objectives / deliverables are:
1 - import SRTM data for (part of) Australia in PostGIS (PostgreSQL)
2 - write several algorithms to estimate the height of any given coordinate tuple (server side), using original STRM grid
3 - display (on the fly, drawing server and/or client side) an altitude profile given a route (a sequence of coordinates)
5 - integrate with the main website (on a separate server)
6 - build simple HTTP API

Secondary goals, if time permits:
7 - scale up to the whole planet
8 - generate altitude contours from SRTM data on the fly
9 - write algorithm to estimate the height of any given coordinate (server side), using intersection with these contours
10 - optimize performance for short and/or long routes

Tertiary goal:
11 - allow profiles to be calculated on a different server