[talk-ph] sanity check for maintaining GPS tracks
totor_osm at yahoo.com
Tue Apr 13 13:23:18 BST 2010
For the cleaning part, I use GPSBabel to:
1. remove low hdop/vdop (and low satellites) points
2. remove close points (<1m) due to traffic-lights, parking-pauses to reduce overall file-size.
3. remove areas I often go or park to avoid clouds.
(this first needs transformation to wpt, then back to trk after filtering)
4. convert raw nmea to gpx
This is the script I use ($1 is input file, $2 is output file):
gpsbabel -i nmea -f $1 -x discard,hdop=2,vdop=3,sat=4 -x position,distance=1m -x transform,wpt=trk,del -x polygon,exclude,file=area.loc -x transform,trk=wpt,del -o gpx -F $2
where area.loc is an exclusion polygon file containing for instance:
--- On Tue, 4/13/10, maning sambale wrote:
> From: maning sambale
> Subject: [talk-ph] sanity check for maintaining GPS tracks
> To: "osm-ph" , "osm-talk"
> Date: Tuesday, April 13, 2010, 9:50 AM
> I have hundreds of GPS tracks. Some
> are uploaded in OSM, some I forgot
> to upload. Some are clean, some are dirty, some are
> squiggly and some
> are a big cloud of points pointing to my house.
> Any advice on how to maintain/clean the tracks before
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