3.4.4.3. Clustering

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clustering Clustering

This tab allows for the Clustering of a Band set. In particular, K-means and ISODATA methods are available.

A report .txt is saved along with the classification, containing the class spectral signature and the spectral distance thereof.

3.4.4.3.1. Clustering of band set

  • Select input band set input_number: select the input Band set;
  • Method radiobutton K-means radiobutton ISODATA: select the clustering method K-means or ISODATA;
  • checkbox Distance threshold input_number: if checked, for K-means: iteration is terminated if distance is lower than threshold; for ISODATA: signatures are merged if distance is greater than threshold;
  • Number of classes input_number: number of desired output classes;
  • Max number of iterations input_number: maximum number of iterations if Distance threshold is not reached;
  • ISODATA max standard deviation input_number: maximum standard deviation considered for splitting a class, for ISODATA algorithm only;
  • ISODATA minimum class size in pixels input_number: desired minimum class size in pixels, for ISODATA algorithm only;
  • checkbox Use value as NoData input_number: if checked, set the value of NoData pixels, ignored during the calculation;

3.4.4.3.2. Seed signatures

  • radiobutton Seed signatures from band values radiobutton Use Signature list as seed signatures radiobutton Use random seed signatures: select one options for seed signatures that start the iteration; the option Seed signatures from band values divides the spectral space of the Band set to get spectral signatures; the option Use Signature list as seed signatures uses the spectral signatures checked in ROI & Signature list; the option Use random seed signatures randomly selects the spectral signatures of pixels in the Band set;
  • Distance algorithm radiobutton Minimum Distance radiobutton Spectral Angle Mapping: select Minimum Distance or * Spectral Angle Mapping for spectral distance calculation;
  • checkbox Save resulting signatures to Signature list: if checked, save the resulting spectral signatures in the ROI & Signature list;
  • BATCH batch_tool: add this function to the Batch;
  • RUN run: choose the output destination and start the calculation;