Last week I attended a training course in Cambridge on Image Exploitation using SOCET GXP. The photogrammetric software, developed by BAE Systems, is the latest release and the successor of the SOCET SET software. As this is going to be the intended software I will be using for my 3D modelling of buildings, and with nobody in the Geospatial Engineering department having any experience with SOCET GXP (SOCET SET is currently installed on the computers), I was chosen as a representative from the University. The majority of the attendees had military backgrounds, two from the Swiss and two from the American military. There was a few from industry, including two from a 3D modelling company in London.
The four day course started with a basic introduction to the software and getting to know our way around the windows. SOCET GXP has made several alterations to SOCET SET, most significantly the interface. GXP has two main windows, the Workspace Manager and Multiports. The Workspace Manager is where all the data is managed, and the Multiport is where the data is displayed. Data is loaded from the Workspace Manager into Multiports. Previously, SOCET SET could only load two images at a time. Now with GXP, four images can be loaded, either as a singular view with the imagery in layers, similar to that of ArcGIS, or in a tiled panel. GXP has also adopted the ribbon menu approach, similar to that seen in Microsoft Word, which makes it much easier to find things compared to SET. After drawing and editing the image, various formats can be used as outputs, for example a screenshot can be exported straight into PowerPoint, shapefiles can be created in a geodatabase, and GeoPDFs can be produced.
After the first two days of familiarisation with the software, the final two days looked at the capability of data extraction, in both 2D and 3D using stereo. Tools in the toolbox are segmented into different types depending on their functionality; draw tools, mode tools (which describe how the draw tool operates) and modifier tools. Cue Cards help explain how to use the tool, making them very straightforward to use. One of the main tools in the software which may prove worthwhile in my project is the Automatic Feature Extraction tool, which can depict building outlines and trees based on a set of parameters. Having only used this tool on lidar data, it will be interesting to see what results it yields for aerial imagery. For 3D extraction, several models exist in GXP, such as planar roofs and gabled roofs. These can usually be utilised by defining a ground point and the rooftop points. Although this is an easy option for modelling, it cannot be incorporated into my work-flow due to its heavy reliant on manual interpretation of ground and roof points. The accuracy of the building is therefore dependent on the analyst.
As well as learning about the software a vast amount of ‘networking’ was undertaken over the four days.
The course has given me an insight into the new and existing capabilities of SOCET GXP and how it can potentially be utilised in my research project.