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Comment by seagreen | Hacker News Reader

Sweet! This means you could have a complete navigation system without a dataplan.

You would still have to roll your own offline geocoder. From my experience with OSM and Oracle's Spatial Geocoder, getting accurate driving directions can be a very 'interesting' process.

Roll your own? Why not use one of the existing widely-used OSM geocoders?

http://wiki.openstreetmap.org/wiki/Photon http://wiki.openstreetmap.org/wiki/Nominatim

Sorry, lost in translation there. I meant deploy an offline geocoder.

Either of those examples I provided can be used "offline" provided you have a local copy of the dataset, which is the given assumption.

Is it possible to embed the geocode data into the OSM dataset? So you wouldn't need to geocode on the fly?

To a first approximation, the geocode data is embedded in the planet file (as address tags associated with some object or another).

But most consumers aren't using the data as organized in the planet file, they are generating extracts based on extent or whatever criteria, and usually processing the data into some data model that is better for the work they are doing.

Thanks. I was curious if not only could you have all the OSM data offline, but if you could have all of the integrated geocoding data offline as well.

Geocoders using OSM are also usually pulling in address range data from TIGER.

The Address Ranges National Geodatabase (~500MB) I'm assuming?

http://www.census.gov/geo/maps-data/data/tiger-geodatabases....

I guess not (but I've never really messed with it):

http://wiki.openstreetmap.org/wiki/Nominatim/Installation#I....

What a nice link.

See also http://www.datasciencetoolkit.org/, which has both a Google-style Geocoder and Street Address to Coordinates APIs. Uses OSM data, and ships as a downloadable VM with all data.

You can. For worldwide coverage you'd need at least 500GB disc space and 2-3 days of data crunching (assuming 32GB RAM, 8 cores, SSDs...) to build the Nominatim database. Photon is using Nominatim's database as input and will take another 2 days (if I remember correctly, met the author last year) to build. (I work on OSM data professionally)

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