[OSM-talk] Delete gpx points in JOSM

[Simon Hewison]

Scott wrote:
> 
> Now this really gets to what was eating at me.  My traces are very dense
> in places where I was moving slowly (under the speed limit :-)
> 
> I was wondering if there was some optimisation occuring to remove points
> that were on a straight line to reduce the density and prevent bloating
> of the db.  If there isn't then, like you say, I will need to edit the
> xml file by hand?  That sounds pretty boring and error prone.  I might
> try to modify JOSM/add a plugin if that's the case.

It's possible to use various switches in gpsbabel to reduce the complexity 
of a GPX file, by removing points that are nearby. Personally, my GPS 
receiver (a Garmin etrex) does this automatically.

see http://wiki.openstreetmap.org/index.php/Making_GPX_Tracks for more details.

> If I upload a trace for an existing road in to the OSM db, is some code
> there going to average my results in to the db?

No, there's nothing doing that at present. It would be rather 
computationally intensive, since it would need to follow all GPS traces 
within a bounding box, and work out that two or more traces look like they 
really were following the same feature, in the same direction (not along any 
nearby parallel roads), before attempting to do averaging. At present the 
trackpoints in the database are merely points, not the full traces with 
context, which is important for doing this sort of thing.

-- 
Simon Hewison