[Talk-GB] Beta release: Address mapping tool

[Rob Nickerson]

Hi all,

As previously discussed OSM UK has been working on a new way of mapping
addresses. We're at a stage where we are ready to share this and ask for
feedback. My thanks to Russ and Pieter for the development work and the
many people who have provided support and advice since we came up with this
idea 12 months ago.

First a recap: The new tool makes use of openly licensed datasets in order
to predict where an addressable point is. To do this we take OS generalised
buildings and land ownership (Cadastral) parcels. The land parcels are used
to split the generalised buildings (e.g split semi-detached houses into
their two parts) and the centre of these split buildings become our
predicted locations for addresses. These are then compared to the existing
data in OpenStreetMap. We check for cases where the point falls within a
building way in OSM, and when OSM already has an address within the
Cadastral parcel. All of this is then presented in the user interface (we
are using MapComplete as it works across desktop and mobile). Contributors
can then add the address following a ground survey.

With that in mind here is the link to the demo tool (in test mode so no
data is written to OSM):
https://pietervdvn.github.io/mc/develop/uk_addresses.html?test=true&z=7&lat=52.92215&lon=-1.87866&filter-to_handle=true&language=en&welcome-control-toggle=true#welcome

A few initial observations:

   1. As it is in test mode, you see some developer debug (e.g. the code
   names for each block in the questions popup). Please ignore this as it
   won't appear in the final version.
   2. It can get slow if it tries to load too much data. If this is the
   case I find refreshing the page at a fully zoomed in position works well.
   3. Currently when you try to import a point you get the option to move
   the location. As the data is coming from OS and the cadastral parcels this
   doesn't make sense. I'm hoping we can get rid of the screen that allows you
   to move the point.
   4. A ref:GB:uprn tag is added if only one UPRN is found within a
   cadastral parcel.
   5. A uprn_count tag is also added. I personally find this useful as it
   is a good indicator of how many addresses a point covers, therefore giving
   a good piece of info to support QA checks. It also can help interpret if
   something like house number "1-6" is six addresses or three (if just odd or
   even numbers). Keen to get feedback on this proposed tag.
   6. There may be some points proposed that are not actually addressable
   locations. Currently you should just ignore these but another option is
   that we have a button to say "Not an address". We could then ask what it is
   and add a noaddress=yes and fixme= tag to OSM. Again feedback on this idea
   is welcomed.
   7. Due to the approach we selected, it does not always offer an address
   point. This is particularly true in city centres and areas with social
   housing. It comes from the lack of Cadastral parcels. We previously
   discounted the raw UPRN data as our source of address locations (due to too
   much noise) so there is not much we can do about this. You can pre-add a
   partial addr:* point to OSM (e.g. addr:street) in another map editor and
   then add the rest of the address using this tool.
   8. It is not yet possible to add a completely new point that is not in
   the pre-processed data. I am curious as to whether this functionality
   should be added or not given that the aim is to share this tool with people
   completely new to OSM.


Finally, for those of a more technical nature, the datasets I described in
the recap section are available as tiled GeoJSONs and MVT tiles. You can
then use these in other places should you wish. For example the MVT can be
added to JOSM (Imagery -> Imagery Preferences... -> Click "+MVT" button ->
paste in https://osm-uk-addresses.russss.dev/addresses/{z}/{x}/{y}.mvt and
add a maxzoom=21). Being a MVT layer, you can right click the layer name in
the Layers side-panel and click "Convert to OSM data" to access it. Don't
upload the whole thing; instead carefully pick features that you want to
use for a ground survey / manual inspection.

I look forward to hearing your feedback on this. The aim is to then get
this in the hands of people completely new to mapping so that we can speed
up the address mapping task.

Thank you
*Rob*
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://lists.openstreetmap.org/pipermail/talk-gb/attachments/20220211/5cadc193/attachment-0001.htm>