How to create

a sample set for image classification

To perform an image classification, a sample set has to be created. Then, you can sample training pixels: assign class names to groups of pixels with similar spectral values and that are supposed to represent a known feature on the ground.

A sample set consists of:

Tip:

When your graphics board is configured to use more than 256 colors, you will use an interactive color composite; then, a background map on disk is not used. For more information, refer to How to create a color composite.

To create a sample set:

By the first two actions, the Create Sample Set dialog box will appear. In the this dialog box, you can specify the sample set's name, and the domain, map list, and background map that you want to use during sampling.

By the last two actions, the Sampling dialog box appears in which you can select an existing sample set, for instance to add more training pixels, but you can also create a new sample set by clicking the little create button. If the create button is used, the Create Sample Set dialog box will follow.

When everything is OK, the sample set editor is started which allows you to select training pixels, show feature spaces, etc.

See also: