OpenStreetMap
I wondered if there was any interest in adding marine features to OSM, or if there was a more appropriate equivalent ("openmarinechart" ??).
I have done some charting of small areas (too shallow/small to be of interest to commercial vessels) but there had been no way to share the data, or even to get it into my GPS as a map (MapDekode to Garmin, ugh!). Generally it's readings from an echosounder, hopefully corrected to Low Water by accounting for tides and transducer depth. I used manual entry, but I presume there are automatic solutions. In OSM, I guess one could add a spot depth as a point with appropriate attributes (units, datum, value)
I also wondered about generating terrain maps from GPS elevation data; there must be quite a lot of user data available now.
Discussion
Awennit n HannesHH di 11 August 2009 ɣef 06:23
http://openseamap.org/
It's currently the image of the week in the Wiki: osm.wiki/ ;)
Awennit n burto di 11 August 2009 ɣef 09:42
Support for marine POIs is just becoming available in mkgmap so in the future
you should be able to generate Garmin marine maps directly from OSM data.
Awennit n alv di 11 August 2009 ɣef 13:11
Do check if it applies in your country: some countries have made "systematic" depth measurements a licensed activity; they consider the data too interesting for hostile army vessels and want to keep some navigable waters a secret - thus the licensed surveyors need to present their data for "cleanup". But if they can't know who you are...
Someone did experiment with generating terrain data from a pile of gpx logs elevation data. I got the impression that only after tens of traces for each road the values start to converge to a reasonable presentation, i.e. without nonexistent hills or cliffs. And only for that road. Sorry, no link at hand.
Awennit n POHB di 11 August 2009 ɣef 13:30
I played with producing 3D images from traces I made while skiing. While they looked OK individually, several days traces contradicted each other about the height. This was with a Vista Hcx which has a barometric altimeter as well as GPS altitude.
Awennit n cantece di 11 August 2009 ɣef 13:34
Hello,
look what they have done here:
http://www.freietonne.de/seekarte/?zoom=12&lat=54.4486&lon=10.30917&layers=B00T
Cantece
Awennit n Skippern di 12 August 2009 ɣef 10:40
You can also help out with looking at Marine Mapping and the marine-tagging proposal. I have had an idea of harvesting ecco sounder data to build a sort of SRTM data source for depths, but havn't got the idea further than random thoughts.
-A