Blom GIS Plug-ins guide – ArcGIS

In another of our useful guides on getting the most out of Blom’s products and applications; today we’re going to take a look at the BlomURBEX™ GIS plug-in for the ever popular ArcGIS.

Similarly to our WMS/WMTS service, a lot of customers aren’t aware that they can load our online data directly into their existing GIS applications. Our range of GIS plug-ins allows users to view not only ortho imagery, but BlomOBLIQUE™ data too. The data doesn’t need to be accessed from BlomURBEX™ either; using the plug-in you can also load in a local library. So if you’ve been supplied an offline library as part of a BlomDESKTOP™ deliverable, you can use this plug-in to access the data with.

Getting Started

So let’s get started. First you’ll need to download the latest ESRI Add-in from our website here >

BlomURBEX ArcMAP GIS Plug-in v4.0
(click to download)

Depending on which version of ArcGIS you have, will depend on the file that you need to download. For this guide we’re going to be using ArcGIS v 10.0, but our plug-ins support up to v 10.2. We have plug-ins for older versions of ArcMap here.
The downloaded file will be an .esriAddIn extension. All you need to do is double-click on it (with ArcGIS closed) to install. You should receive this prompt;

Install prompt

Simply click ‘Install Add-In‘ and it will copy all the required files to your ArcGIS plug-in directories. That’s it, done!

Now when you next launch ArcGIS you will need to add the BlomURBEX toolbar to begin using the plug-in. You can find it listed in ‘Customize > Toolbars > BlomURBEX‘. Make sure this is ticked;

BlomURBEX GIS toolbar

Now, all being well you should hopefully see two new buttons appear in your toolbars;

You can drag them around and put them where you like. The two buttons perform two features:

Open BlomURBEX Viewer
This will open the window to view the imagery

Centers BlomURBEX Viewer on a point
Clicking on this will enable a crosshair, which when clicked in the main Arc data frame window, will load the Blom imagery for that location.

Using the plug-in

Now we’ve got our plug-in installed and set up, it’s time to start using it. I’ve loaded in some basic building polygons from an area around Queens Square in Bristol, .


Now lets take a look at the imagery around that location. Go to the button ‘Open BlomURBEX Viewer‘ and click on that – a dockable window should now appear;

BlomURBEX viewing window inside ArcGIS

You’ll notice that this is black – don’t worry, we just need to set up the datasource in the settings first. Just click on ‘Change Settings‘ in the window, then go to ‘BlomURBEX Datasources‘ and type in your login details if you want to access the data online via BlomURBEX™, or browse to the location of your offline library. For this purposes of this guide we’re going to access it online;

Setting up a BlomURBEX connection

When you’ve typed in your login, press ‘Add Datasource‘ and it will add it to the list of currently enabled sources. Don’t worry too much about the other settings, these can all be changed later on.

The next important step is to change the coordinate system in the ‘Linking‘ tab. This must be the same as the coordinate system you’re currently using in the main ArcGIS workspace. This so that when coordinates are queried in Arc, the plug-in knows the type of coordinates to search for and what imagery to display.

Make sure coordinate systems match

In our guide we’re using OS British National Grid (OSGB 1936) polygons in an OSGB 1936 data space, and I have manually set the plug-in to use EPSG Code 27770;

Searching for EPSG codes

If you’re not sure which EPSG code you need, a great place to search is on the Spatial Reference List website.
Obviously if you’re working in a different coordinate system, make sure you change it to the correct one, but remember that the two must match.
Now when you hit ‘Save Changes‘, you should hopefully see some imagery. Click on the button ‘Centers BlomURBEX Viewer on a point‘ and the cursor will change to a red crosshair, now choose somewhere in the main ArcGIS data frame and click. The appropriate imagery for that location will now be displayed in the plug-in viewer window;

BlomURBEX data inside ArcGIS

If you’ve used either BlomWEB™BlomDESKTOP™ or any online mapping system before, you should easily recognise the tools and understand how to use them. One the left of the window you have the zoom and view orientations, and across the top you have the following tools;

  • Location – Returns coordinates for selected point
  • Distance – Measures point A to B
  • Height – Measures vertical heights from bottom to top
  • Ground Distance – Measures point A to B including DTM elevations
  • Bearing – Angle to true North
  • Area – Measures area of a drawn polygon
  • Elevation – Returns height above sea level for selected point
  • Façade Area – Measure vertical areas
  • Diagonal – Calculates the hypotenuse of a drawn triangle
  • Clear – Removes all measurements

You will notice that there are blue and red lines appearing in the ArcGISdataframe;

The blue line indicates the extents of the currently selected image, so in this case because we’re viewing a North-facing BlomOBLIQUE™ image, the blue line shows the full extents that this single image covers.
The red line indicates the extents shown of the image we can see in the viewing window.

One of the other many features available in the plug-in, is the ability to overlay vectors onto the imagery. So again, using our building polygons, we can see these directly on the imagery itself. To do this simply click on the ‘Overlay Vectors‘ tool in the viewer window. This will draw the polygons in the imagery window;

Vector overlays in Blom viewing window

You can change the opacity of the polygons in the ArcGIS display settings to make them most visible for you. Then just hit refresh in the plug-in viewer window to update them. The style of any vectors in the ArcGIS workspace will be mirrored in the plug-in window.

If one window isn’t enough, you can open up to four more views, to have five simultaneous and fully synchronised views of the same area.

Four synchronized views

That covers the basics of how to use the plug-in. In the future we’ll bring you some more guides on how to use some of the more detailed functionality such as saving measurements and exporting images. So keep an eye out on the Blog for more information.

If you’d like to find out availability and pricing for our BlomURBEX™ datasets, please contact your local Blom office via our website.