Sunday 12 December 2010

Maps of memorials

I spent a bit of time looking at the UK National Inventory of War Memorials web site looking for memorials to add to OSM. I realised they need a lot of work to improve their data so I volunteered to help.

I received a set of instructions so I waded in. The job is to update a holding database that will be used to update the main database in time. The holding database has a list of memorials and the idea is to enter the information about people who are mentioned on the memorial, adding as much detail as is available. The holding database has links to data, either .TIF files that hold scanned images or PDFs that hold photgraphs. The scanned images are often hand-written notes from people who have visited the site. This is screaming out for crowd-sourcing. The disconnect between the person who visited and the person who edits is what has caused the errors and omissions that volunteers are trying to solve, but using the same disconnected system.

The first .TIF file I opened had 1667 pages of scanned images, relating to even more memorials and because they are just bitmaps there's no searching or index available. The first PDF I opened had a horrible photo that was barely readable. The memorials I am part-way through has 1200+ names on it, all need amendments.

It is, however, very satisfying being able to correctly name and identify these men (almost exclusively men in WWI) making it possible for people to trace relatives' memorials. I will stick at it.

The coordinator does seem interested in adding a map to their web site. I knocked up an example OSM map based on extracted UK, OSM data using historic=memorial and that quickly showed that differentiating war memorials from all kinds of other memorials is not straightforward. If you are adding a war memorial please add a tag memorial=war_memorial to differentiate it from others such as blue plaques. 

I want to encourage them to use an OSM-based map, using their data and then they may release their data for use in OSM generally. I have yet to break it to them that every memorial will need a location and the 6 figure OS grid reference they hold for some of them is nothing like accurate enough since it only ties the memorial down to 10,000 square metres, and that's if it's correct. A crowd-sourcing approach to position the memorials more accurately might be in order.