When Written: Dec 2011
Mapping has always held special fascination for me and from an early age I studied the large yellowing maps on the wall on the primary classroom. These graphical representations of the world showed a previous era, with a lot of the countries coloured in a pinkish red to indicate that they were part of the British Empire.
At this point I must clarify that these maps were old when I was at school, as I’m not THAT old ! Honest! I would study the various countries and wonder what they were like, hoping that one day I might be fortunate enough to visit some of them. Understanding the location of countries and their neighbours became important as I grew older and developed an interest in history and current affairs.
Apart from the mass of information stored in a graphical representation of our world, the artistic beauty of maps appealed to me, from the highly stylised medieval creations with their sea monsters and dragons drawn in various places, to the incredible detail of the modern Ordinance Survey maps that we are all familiar with. With such detail contained in these modern maps it is fun to examine them closely to visualise areas and to discover features of the landscape and that might be interesting to visit. On my first visit to America I was disappointed at the lack of detail in their road maps; sure they were perfectly adequate for navigation, but in just the same way that whilst a McDonalds will fill the basic needs of your hunger it is not the same experience as a meal at somewhere like Mirabelle.
Along came Google with its ground breaking mapping technology and we were all hooked, but the maps, whilst showing the basic information, are still lacking in the sort of detail that would give me my ‘cartography fix’. switching to satellite view helps to provide detail but only at a superficial level, you can’t identify a public house, toilets, or picnic places to name three that spring to mind. So why do we have to put up with a regression in cartography art just because we are accessing it on-line? The reason is not one of bandwidth but of licencing costs. I have mentioned in the past the crazy situation in this country where the mapping is done by a government funded organisation using Tax payer’s money, but this data from the Ordinance Survey is only available at huge licencing costs, even to Government bodies.
Without doubt this attitude has in past has held back companies wanting to use UK mapping in their products. Most use Google maps but this has its issues with accuracy of Post Codes but this is still not the same as having the raw data for your company to process into your application. Thankfully there has been for some time a very active movement to encourage a change to this situation and to bring the UK mapping opportunities more in line with the US and the rest of Europe. This has finally happened with the release of The Ordinance Survey’s ‘OpenData’ initiative https://www.ordnancesurvey.co.uk/opendatadownload/products.html .
The initiative is part of the Government’s plan to make the workings of the UK government more transparent and to put a lot of this information on-line, the site http://data.gov.uk has a wealth of interesting information in it as well a pile of ‘apps’ for both browser and smart phone from ratings of schools to care homes as well as a journey planner using public transport and it is worth checking it out next time you have an hour or two to spare. The Ordinance Survey has made lots of mapping data available as well as the UK Post Code to Easting/Northing database, and it is all free for a lot of uses. Obviously you need to look at the licence terms to make sure that your application qualifies, but without doubt this is a move in the right direction.
However don’t expect things to be total plain sailing as a lot of this data is in a format that will make it necessary to manipulate it further before it is of use as I discovered. Take for example, the Post Code data which is provided as a series of CSV files, each one for a group of codes, so you have, for example, one sheet for codes starting ‘AB’ and the next file starts at ‘AL’ the next at ‘B’ and so on. So you would probably need to combine these before you start, not a big issue, but looking closer at the data you will notice that the postcode areas are located by Eastings and Northings, so this will need to be converted to Longitude and Latitude for most mapping solutions, all frustrating stuff. The mapping data is even more obscure unless you are really familiar with such stuff.
GIS are providing low cost mapping using the Ordinance Survey Open data
One company, who in the past has offered me advice on mapping, is GIS Mechanics so I was pleased the other day to get a call from them to keep me up to date of their latest project which has involved six months of work. What GIS Mechanics (http://www.gis-mechanics.co.uk) has done is take the Ordinance survey data and generated a series of tile images and build a viewer using the open source ‘Open Layers’ API (http://openlayers.org/ ) .
To understand the significance of this you need to understand that most software mapping solutions create their maps by combining a series of images which are in the form of a series of square tiles at different resolutions. This way maps can be built on the fly without the huge complication of trying to draw them from a series of vector based objects with their points defined by the mapping data. So, armed with a collection of these tiles and a piece of JavaScript , GIS Mechanics has built a way of displaying Ordinance Survey quality maps in your application (http://www.gis-mechanics.co.uk/index.htm?http://www.gis-mechanics.co.uk/intro.htm). The size of all these 5,900,689 tiles is 48G but it runs quite happily on a basic shared web server without any expensive back end technology.
GIS Mechanics has made this collection of images plus the software to display them available for £1300 with £500 per year afterwards for updates if required, so you can use these maps within your own application be it desktop or web based. This is currently much cheaper that the other offerings out there, where Ordinance Survey, for example, charge £13,000 per machine per year. If you just want to use GIS Mechanic’s system on your web site without having the data on your server then the charge is £25 per year per website. GIS Mechanics has also taken the now free Postcode data and added longitude and latitude to it to make it more useful in mapping solutions and sells this data for £30, considerably less than the offerings previously available,
This data does not contain addresses, that is still a very expensive chargeable product from the Post Office . GIS Mechanics is also working on a .NET control that will offer the same functionality within .NET solutions, certainly a busy company and one to watch if you are in need of any mapping technology.
Article by: Mark Newton
Published in: Mark Newton