[mapserver-dev] RFC-108 : heatmap generation

thomas bonfort thomas.bonfort at gmail.com
Thu Jan 30 13:52:14 PST 2014

Just a side note related to the specifics of your gpx requirements...
your actual input data is the sample points, not the lines that link
the points one to another. From an information theory point of view, I
believe that a heatmap created just from the gpx sample points will be
more accurate than a heatmap that assumes that each point is connected
to its neighbour by a straight line. Of course this only holds if your
gps samples points at regular time intervals, i.e. does not apply some
kind of simplification to suppress points along a straight line.


On 30 January 2014 22:12, Basques, Bob (CI-StPaul)
<bob.basques at ci.stpaul.mn.us> wrote:
> Thomas,
> Just one suggestion related to features used for clustering, can you consider using LINE features as well.  My particular need could use points as described and probably still work nicely.  My specific need is for applying heat mapping to trail (GPS, Average Daily Traffic) lines, these lines are generated from points sequences though, so this would still be doable as RFC describes.
> There are occasional instances where long segments are introduced into the GPS data collections where a GPS lock goes missing for a while, these long lines are the things I would like incuded in a heatmap output.  Maybe there is a way to interpolate some points along a line that would still work with the scribed system as another mode of processing.
> Good stuff all around either way.
> History trivia, ask Steve L. sometime, about some heat-map work we did more than ten years ago now for an online mapping interface.
> Bobb
> -----Original Message-----
> From: mapserver-dev-bounces at lists.osgeo.org [mailto:mapserver-dev-bounces at lists.osgeo.org] On Behalf Of Thomas Bonfort
> Sent: Thursday, January 30, 2014 10:58 AM
> To: mapserver-dev at osgeo.org
> Subject: [mapserver-dev] RFC-108 : heatmap generation
> Devs,
> please have a look at RFC-108 [1]. The associated code and the RFC are still beta, so there's still plenty of room for modification or remarks.
> best regards,
> thomas
> [1] http://mapserver.org/development/rfc/ms-rfc-108.html
> _______________________________________________
> mapserver-dev mailing list
> mapserver-dev at lists.osgeo.org
> http://lists.osgeo.org/mailman/listinfo/mapserver-dev

More information about the mapserver-dev mailing list