To perform feature extraction on a different band or bands than what are shown in the display group:

1. Select one of the following:
• From the Vector Parameters dialog menu bar, select Mode > Intelligent Digitizer Parameters.

• Right-click on the display group and select Intelligent Digitizer Parameters.

  The Intelligent Digitizer Parameters dialog appears.

2. Click Select Intelligent Digitizer Input Bands. The File Spectral Subset dialog appears.
3. Select the band, or bands, to use for linear extraction. If you want to use multiple bands, it is recommended that you select six or fewer bands. Using more than six bands slows system performance.
4. Click OK. ENVI uses the bands you specify for the feature extraction. Changing the bands to use from the File Spectral Subset dialog does not change the bands that appear in the display group.