Processing classified output

In the classified output, some misclassified isolated pixels or small regions of pixels may exist. This gives the output a "salt and pepper" or speckled appearance. Post-classification processing refers to the process of removing the noise and improving the quality of the classified output.

The ArcGIS Spatial Analyst extension provides a set of generalization tools for the post-classification processing task. This task involves three steps. Each step is based on a Spatial Analyst tool from the Generalization toolset.

  1. Filtering the classified output.

    This step removes the isolated pixels or noise from the classified output. The Majority Filter tool is used.

  2. Smoothing class boundaries and clumping classified output.

    This step smooths the ragged class boundaries and clumps the classes. The Boundary Clean tool is used.

  3. Generalizing classified output by removing small isolated regions.

    This step reclassifies small isolated regions of pixels to the nearest classes. The Region Group, Set Null and Nibble tools are used.

Related Topics

12/16/2013