Segmentation

Image segmentation covers techniques for splitting one image in several homogeneous regions. The Segmenter interface implements methods to segment a raster.  The available methods in TerraLib are:

Input:

Output:

It is accessible through:


    Raster Processing > Segmenter... (list of all raster layers)


This wizard consists of the following steps:

    Wizard Page 1 - Selection of the layer with the desired raster (Layer Search)

  1. On the List of Layers select the raster layer to apply the segmentation. 
  2. Optionally use Filter By Name  field giving part of the layer name to help find the layer in the list.
  3. Press Next  to go to next step or Cancel to close the dialog. 

    Wizard Page 2 - Segmentation interface

  1. Type -  Choose the method of segmentation and set the specific parameters required.
  2. Common Parameters:
  3. Select the Input Bands to be segmented by checking its box. For Baatz method, its is also possible to change Weight (The weight given to each band (note: the bands weights sum must always be 1) or an empty vector indicating that all bands have the same weight.)
  4. Preview - optionally click on to check the segmentation of a small box of the image.
  5. Press Next  to go to next step, Back to check the previous wizard page or Cancel to close the dialog.  

    Wizard Page 3 - Segmentation Advanced parameters interface.

    Optionally, use this page to change default values of  advanced parameters related with performance.
  1. Block options:
    • Enable block processing: If checked, the original raster will be split into small blocks, each one will be segmented independently and the result will be merged (if possible) at the end.
    • Enable block merging: If  checked, a block merging procedure will be performed
  2. Thread options:
    • Maximum block size: The input image will be split into blocks with this width for processing, this parameter tells the maximum block lateral size (width or height). The default behavior, the size will be defined following the current system resources and physical processors number.
    • Maximum threads number: The maximum number of concurrent  threads. The default behavior is: automatically found.

    Wizard Page 4 - Output Raster information

  1. Raster Info - First press and inform the folder where the resulting file will be saved.
  2. Name - inform the raster name.
  3. Extra Parameters - if there are some, see the details on how to inform then here.
  4. Press Finish to save the resulting segmented raster or Back to go to the previous wizard page.