Image Labeling

The connected components labeling produces as an output an image model IL, with vectorial representation of Labeled Image, similar to the function of image segmentation.

The labeling is performed on the active IL, usually over a classified image (image model) or raster related to a thematic image (thematic model). In both cases, you can control the area parameter (in pixels), referring to the input/output Layer, besides the smoothness of lines to be created.

The Input Layer can be changed by removing polygons with areas smaller than a given value, substituting the class or color for one in its neighborhood. The Output Layer, where the labeled image will be created, allows the elimination or not of the smaller areas.

Connected Components Labeling:

  • activate an Information Layer from a Thematic model (with a Raster representation) or Image model (with a classified representation) on the Control Panel;
  • click on Image - Connected Components Labeling... or Thematic - Connected Components Labeling... on the main menu;
  • at the window "Connected Comp. La." observe if the input layer corresponds to the active IL;
  • select on the Categories list, which one should receive the labeled image IL. Observe that only Image model ones will be available. If there is not an appropriate category for labeling, create a new one at the Data Model option ;
  • type in a name for the Output Layer: ;
  • type in the value in Area (pixels) at the Region Merging and check the one you want to eliminate (Input Layer or Output Layer);
  • if you want the Arc Smoothing for the Output Layer, click Yes;
  • click on Apply.

Notice that the InfoLayer will be available at the Control Panel after this procedure.

The figures below show the labeling of connected components performed over an image model IL, where areas smaller than 40 pixels where eliminated from the Input Layer. The output labeled image kept the lines which involved the deleted polygons.

Classified Image (original)

Image with deleted areas

Output Labeled Image

 

See also:

Raster Edition