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Data Processing (Data Cleaning)

In this page one of the two possible scenarios defined for the use of the EMS is demonstrated. This is the Dataset Cleaning : a input dataset should be without gaps, but there are small gaps in between the individual features that need to be filled.

The complete process is detaied here in order to goal two objectives:
  • Show the OpenJUMP WPS client usage
  • Show the Dataset Cleaning functionality of the HUMBOLDT Edge Matching Service.

Load input datasets and show the problem to solve

1. Open the files to edit (File --> Open File...).


Loading datasets

Note: If datasets are in gml format, you will need to supply a Jump template. See here how to create a Jump template

2. In this case, Protected Areas from Portugal (green) and Spain (red) are used.


Datasets loaded

3. When zooming in, gaps in the datasets are visible.


Dirty datasets

4. This picture shows a gap in the polygon for the Spanish Protected Area. Data cleaning is therefore required.


Gap in the Spanish Protected Area

Connect to WPS server

1. In the toolbar, click WPS Client -> Add WPS


Adding Web Processing Service

2. Enter the URL to your WPS service. In this case, http://localhost:8080/wps/WebProcessingService. Press OK.


Connecting to the WPS Server

3. Check that that the service has succesfully been connected (bottom left) and execute the WPS (Click WPS Client --> Execute Process).


Successful connection

Use Edge Matching Service

1. After click Execute Process a window with the processes provided by the service appears. Choose the HUMBOLDT Dataset Cleaning Process. This process will remove the gaps and overlaps in the dataset. The Describe Tab is describing the process, i.e. DescribeProcess (OGC). Please read it.


DescribeProcess of the Dataset Cleaning

2. Press the Execute tab. Choose what dataset to clean and fill in the maximum distance of two edges to be matched:
  • data= the geometry to clean,
  • metadata= metadata document related to the dataset to be aligned,
  • distanceTolerance= maximum distance of two edges to be matched.

The desciption of these inputs are given in the DescribeProcess document showed in the above step.


Input parameters on Dataset Cleaning example

See results

1. Results of Clean Dataset. The gaps and overlaps are removed. The result layer Process Results overlays the protected area layer.


Input vs Result

2. Which becomes more visible when the protected area layer (Zonificacion_PN..) is deactivated.


Spanish dataset without gap

3. Perform the same process for the other dataset and the results should be as the following image.


Input datasets cleaned

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