Category Archives: Geodata

Better than the commercial product?

Critics of OpenStreetMap have in the past used various arguments for why they believe the project can never be a success. Often quoted is the concern about data accuracy and completeness and another is about how changes in our world are noted and managed. Well it’s clear we needn’t worry too much as some great work by OSM contributor Dair Grant clearly shows.

Dair made a comprehensive and detailed comparison of his completed map for Haywards Heath, Sussex with that of the TeleAtlas derived Google Map and found 89 apparent differences, that’s an astounding number for a small town.

Demise of the humble segment

Its official. As of Sunday 7th Oct 2007 the OpenStreetMap segment is 410 Gone. It had a brief and at times difficult life sandwiched between nodes and overshadowed by ways. But shall we miss it? I think not. For the uninitiated, OSM moved to the new 0.5 server code at the weekend thanks to the hard work done by Frederik, Gabriel, TomH and others. The data model now consists only of the node and way plus the new Relationships (relation), which offers a whole new data creation experience. The majority of the OSM platform tools have been migrated to support the API v0.5, which is not backwards compatible with v0.4 tools. Both potlatch and JOSM work with the changes although for JOSM you will need to download the latest version.

Mapping Parties, Demos Talks – Its all happening in Victoria, Canada

by Nick Black

OpenStreetMap is coming to Victoria, Canada. There’s going to be a load of OSM related activities in the city that boasts Canada’s mildest winter temperatures.

OpenStreetMap Mapping Party Sat 22nd – Mon 24th September
OSM mapping around the conference area Monday 24th September
OSM talk at FOSS4G Tuesday 25th September
OSM demo session Wednesday 26th September
Post FOSS4G Code Sprint Friday 28th September

So if you are in the area, come along and join in the mapping fun. The usual stuff applies – its open to anyone, we have GPS units, its fun, sign up here

OpenAerialMap – Community contributed aerial imagery

By Nick Black

The recently back-from-the-brink-of-death Slashgeo, links this morning to an interesting open geodata initiative – OpenAerialMap. As the name suggests, OpenAerialMap is an attempt to aggregate as much free aerial imagery as possible. This makes a lot of sense. In the same way that I can go out with a GPS and map my street, I can fly my UAV over my street and gather imagery, safe in the knowledge that my neighbour a few streets away is doing the same thing. We join it all up and get a free image map of the world.

A technical problem to solve will be to rectify images to make them usable with other mapping/GI systems. This requires the use of ground control points, either gathered from existing maps or imagery (as seen in the MetaCarta rectifier) or based on GPS positions. Right now, OpenAerialMap have opted for a one at a time approach – with users uploading an image and manually rectifying it – presumably against public domain, or maybe even OpenStreetMap maps. None of this is actually up and running yet – the project is still in the planning stage.

The licensing of the project is unclear – there’s a lot of talk about freedom and open source, but nothing concrete about what the license actually is. Aa OAM haven’t started accepting uploads yet, there’s still time to choose a license that will maximise the usefulness of the tool they are creating.

As you would expect, OpenAerialMap talk a lot about community on their wiki. Unfortunately, as of this morning editing the wiki has been frozen temporarily until we clearly define appropriate use. So in the mean time, you can subscribe to the mailing list to find out more.

AND donate entire Netherlands to OpenStreetMap

“Automotive Navigation Data” (AND) [since renamed GeoJunxion] is a leading provider of location, routing, mapping and address management are donating a street network of the entire Netherlands. Yes, an entire country.

This is basically phenomenal.

We’ll have our first country complete from this data, which AND and I want to work with the community to import. This is not least because fantastic work has already been done in Amsterdam and elsewhere by the Digital Pioneers supported openstreetmap netherlands community. AND will be at the State of the Map, and you should be too 🙂

Here’s the press release:

AND and OpenStreetMap join forces to create digital maps
Rotterdam – AND Automotive Navigation Data has agreed with the OpenStreetMap Foundation to donate digital maps of the Netherlands, China and India to the OpenStreetMap community. The aim is to create the most up-to-date map in the market. With this partnership AND recognizes the power of a community and the Web 2.0 developments.

OpenStreetMap gives the community the opportunity to create maps with up-to-date geo-data and shows the results immediately. Pure community collaboration at its best. “Overall we want to enable users of mapping data to also be contributors, from reporting errors to doing full surveys.” According to Steve Coast, one of the founders of the OpenStreetMap project.

“It is known that a small percentage of a map is not representing the present situation. With the help of the community AND aims to close this gap and be able to a deliver a map that is 100 % correct.” According to Maarten Oldenhof, CEO AND Automotive Navigation Data.

According to Wikipedia Web 2.0 refers to “a perceived second generation of web-based communities and hosted services – such as social-networking sites, wikis and folksonomies – which facilitate collaboration and sharing between users.” AND is busy today with the process of bringing maps online with the possibility of online user generated updating. “We think Web 2.0 will be the ultimate tool for map updates. With this partnership we work with the people that have a keen insight into how a community works around maps” according to Maarten Oldenhof.

Initially, AND will make its street level data of the Netherlands and the major road networks of China and India available to the OpenStreetMap community. “We are very happy with the map donation of AND. With this additional map data we hope to create a bigger mapping community and be able to cover more and more areas” according to Steve Coast.

[AND was since renamed GeoJunxion in 2020]

Holland is 5% done

The Dutch Statistics department calculated that there is 141,251 km of road in the Netherlands. In the OSM database 6,833 km are accounted for. That is almost 5%!

From the big cities, the following is done:
1. The Hague: 545 km
2. Amsterdam: 403 km
3. Utrecht: 313 km

Rotterdam is almost white space. It needs another 2,100 km! You can help this weekend!

The top 10:

1. Nuenen, Gerwen en Nederwetten 46.8%
2. Heiloo 45.8%
3. ‘s-Gravenhage 43.5%
4. Leidschendam-Voorburg 38.8%
5. Schermer 32.9%
6. Delft 29.2%
7. Utrecht 27.0%
8. Boxtel 26.8%
9. Waterland 24.4%
10. Bussum 23.9%

We are almost done in Bennebroek: only 21 km to do! (of a total of 21 km).

OSM Weekly Review – Mooses on Rails

The talk of the town this week has been the long awaited Ruby on Rails port. A developer’s meeting in Oxford on Saturday gave the opportunity to finish off some loose ends in the existing Rails code, integrate Potlatch, as well as experimenting with PostGIS. Version 0.1 of OpenStreetMap was written in Java, then re-written in Ruby and over the last 6 months all the server code has been ported to Ruby on Rails. The good news is that the new site has been deployed and is running. There have been some teething problems, so if the site is unavailable when you take a look (if you get a 500 error), come back in half an hour or so. Because the way that the API works in 0.4 is slightly different from 0.3, applications that use OSM will have to be updated. To use OSM 0.4 with JOSM, you’ll have to download a new version from the JOSM homepage. Other apps like Tiles@Home and the Applet are being updated and users should check their wiki pages for updates. There’s going to be an OpenGeoData post dedicated to the Rails Port later on this week – so stay tuned.

Anyone who reads OSM-Dev or OSM-Talk will have experience the "we should use PostGIS" scenario. The familiar story has taken a new twist with Robert Monro, Schuyler Earle and others working on bringing the benefits of PostGIS to the OSM Rails port. PostGIS is a spatial database – a sort of swiss-army knife for all things geospatial. It can suck in numerous formats of spatial data, and speeds up spatial queries like "what is next to here?" or "what is inside this box?". A major problem with using PostGIS has been its lack of support of Topology. Topology is about connectedness – what connects to what and what, what side of A is B on – and OSM’s database is topologically constructed, which has limited the usefulness of tools like PostGIS. By writing customised functions for PostGIS, SDE and Robert Monro hope to get around the problems with PostGIS whilst maintaining OSM’s data model. There is more information here and source code here.

Devout countryside man, Nick Whitelegg, brought this post to the attention of the mailing list. It seems that a lot of walkers don’t see the value of OSM and have a "if its not complete I don’t want to know" attitude – something that rings true of a lot of people that OSM users encounter. Mikel makes a good point that the continued mapping of the countryside by the OS is currently far from guaranteed. If walkers want up-to-date maps they are either going to have to pay a lot more for them, or get them from other sources. If you are a walker or countryside user, take a look at Free-Map, which provides editable maps optimised for countryside users, based on OpenStreetMap data.

A rainy bank-holiday weekend in the UK isn’t great news for most people. For OSM users it meant one cool new tool and one interesting use of a wiki page. The cool new app is David Earl’s name search, which runs off OSM data. The search algorithm is impressive, to say the least. Try searching for your local pub – actually that’s a bit easy – try putting the tool to the test. Prizes for the most bizarre, correctly returned search posted to the comments of this post.

Are you the Moose? Take the OSM Purity Test and find out.

By Nick Black

Week 16 on OSM – From Essen to Blue Seas and Bicycles

Its been a little while… Holidays and all that, but at least a tiny bit of Portugal is now mapped, and I’ve found out conclusively that my kids don’t find it amusing anymore to drive twice round a roundabout!

The Essen developers Workshop has been and gone (it has been a while!). A great weekend by the sound of it – pick up the results here – and if you wondered what happened to the code in subversion, a big restructuring (for the better!) happened. The code’s still there, but more logically laid out. It will be interesting to see what will come out of the UK workshop in Oxford next weekend.

Its been a good week for the osmarender layer on coastlines, again brought up at the Essen workshop. The threads Blue sea tiles, speckled oceans, & too much blue give an indication. So, thanks to Frederick’s work on a pre-processor to handle colouring of coastline tiles the coast is looking rather spiffing. Its great that (I guess) everyone who lives near the coast or had an interest in a bit of coastline made sure the coastline ways were fixed for their area (I know I did!). In fact its been such a good week for osmarender that there was a suggestion to create a separate osmarender-dev mailing list for it!

With a nod to Shakespeare, the thread titled: Users, contributors and developers, (… I come to bury columns; not to praise them) is worth a read in that it covers some of the ethos of OSM and how the simple approach to mapping is working very well. It then goes on to discuss the idea of a ‘third column’ to give namespaces to attributes that was brought up at the Essen workshop.

Watch out for The Rails Port of the server/API coming to a machine near you real soon! Announced by Nick Black on dev. This is going to have a big impact on OSM pretty quickly as its going to make it much easier for the devvers to tinker quickly in a safe environment.

Everyone loves animations!?! Dave has been making snapshots of progress on London over the last 6 months. You’ll have to follow the link to go to the animation.

Placenames disappearing! Its been discussed for a while, but David Earl noticed as you zoom in the slippy map that different names appear and disappear. Its a general problem with what to render at different levels, but it is an interesting discussion on what should be rendered at what level, and what should be considered important for rendering.

Languages for streetnames… The thread on Bilingual street names is a useful discussion on how to tag streets where there are two languages spoken, particularly where in some regions one of the languages is rarely used (we are talking parts of Wales here). Surprised there were no comments about Canada….

If you are one of the out-on-the road mapping types its frustrating to have to stop/start to make notes of a road, the streetname or whatever, so if you have a PDA running windows mobile, you might want to look at the thread on Audio mapping with a PDA and the wiki page that came out of it here.

Maplint I guess is the first really specialised map, but dare I say it, rather geeky! But – hey – that’s what its all about – very specific maps for specific purposes. Now with better cycle-specific tagging being discussed at Cycle route planning using OSM we will soon be getting really personal maps for cyclists. This is what OSM is all about, really personal maps.

And finally, if you want to spread the word on OSM look no further than Andrew’s question on presentation materials – its all there, including a lovely map by Steve Chilton. So there are no excuses now – go forth and promote!

by Barry Crabtree.