From Open Foris Wiki

Jump to: navigation, search

oft-clump - Connected Component Labelling

Add spatial coherency to existing classes by combining adjacent similar classified areas

Usage: oft-clump <-i inputfile> <-o outputfile> [-b band] [-um maskile] [-h help]

-b band = use determined band of the image
-um maskfile = use maskfile and process only areas having mask value > 0


  • Oft-clump is meant for separating uniform regions in a class image.
  • You may obtain such a class image by using e.g. oft-cluster.bash, oft-kmeans or oft-nn.
  • The program looks for similar and adjacent class values in the input image and gives each area an own id.
  • NOTE: For the benefit of users running the script using the older version, where the datafiles are based on the file order instead of options -i and -o, the program can still be used that way.
  • An example of the aim of this program is seen in the image below.
    • Colors represent class values
    • After clumping: pixels with identical class values, but are not spatially connected will have a different id


  • Open your working directory using
cd /home/...
  • To run the oft-clump we use the Input: landsat_t1.tif, Output: clump.tif:
oft-clump landsat_t1.tif clump.tif

Back to Open Foris Toolkit Main Page

Back to Tools & Exercises

Personal tools