OpenStreetMap
I picked up a Garmin eTrex Vista Hcx last week, as my Zumo 550 just wasn't going to cut the mustard in areas without USGS Urban Area coverage; the tracklog sample rate is too rough. On the Vista I set the tracklog interval to 1 second; a 19-mile bicycle ride gave me a track with over 9,000 points, over 1GB in size :)
It turns out that another tool I own (ExpertGPS) does a good job of simplifying and manipulating GPX tracks, so I reduced that to 122KB and about 1,000 points. At that level I didn't feel so bad about converting it to an OSM layer (in JOSM) and uploading it. (I did clean it up a bit). Although it most cases so far I've been tracing my routes in JOSM on the USGS Urban Area map, I think this might be my new M.O.
Subject of today's mapping: Alameda Creek Trail, beginning at Coyote Hills and including at the other end a trip through Quarry Lakes Regional Rec Area in Fremont.
Umræða
Athugasemd eftir SuborbitalPigeon sett inn 9. desember 2008 kl. 01:05
It must be impossible for 9000 points to be a Gigabyte without each point having a lot of data logged. Are you sure it was that big?
Directly uploading GPS data as OSM data is frowned upon.
Athugasemd eftir davetoo sett inn 9. desember 2008 kl. 02:45
Indeed, I misread the file size by three decimal places, but not the number of trackpoints. I am trying to find a compromise between laboriously hand-tracing the features on the Urban Area DOQ (which I won't have most places) and just dumping raw GPS data into the map. The high sampling rate is important for some of the complex footpaths and cycle paths I'm mapping. I may be able to split the tracks apart on either side of the very complex bits and simplify the straighter bits even more.