[OSM-newbies] gps noise in osm database

[Richard Weait]

On Sat, Mar 6, 2010 at 4:08 AM, Paul Johnson <baloo at ursamundi.org> wrote:
> Jonathan Bennett wrote:
>
>> No. GPS traces are just evidence, or a guide, and shouldn't be
>> interpreted literally. If they look messy, it's OK, since they're only
>> used for tracing. The amount of work needed to clean up the traces would
>> be massive (it would need to be done by hand), and we'd gain very little
>> -- it doesn't generally affect the accuracy of mapping.
>
> Surely there's an automagical way to suppress bird's nests.

gpsbabel filters simplify and discard sort of do this, but not exactly.

gpsbabel position filter will allow you to remove points within
$distance of a specific location, so that's good for removing a cloud
around your customary home location.

I don't see a filter that both leaves 1/second points in place and
reduces clouds from stationary receivers.

Perhaps you'll be inspired by filter_skeleton.c to write an ideal
anti-birdsnest filter for gpsbabel?

Once created, I can see the advantage of using such a filter.  Using
that filter blindly on the already donated traces seems unwise.
Perhaps a method can be found to selectively apply such a filter when
viewing traces?

Also, the imperfections of gpx track files do remind us that the track
file is not a complete survey.