Use Forest Cover Classification to classify areas of forest cover in multispectral or hyperspectral reflectance imagery, using information from red and red edge or near-infrared bands.

You can also write a script to perform forest cover classification using the ForestCoverClassification task.

The algorithm classifies each pixel as forest or not using Forest Cover Index 1 (FCI1) or Forest Cover Index 2 (FCI2), with an optional threshold based on the NDVI value of the pixel. The algorithm then optionally performs classification sieving and clumping to remove speckle and small clusters within the classification.

Reference: Becker, Sarah J., Craig S.T. Daughtry, and Andrew L. Russ. "Robust forest cover indices for multispectral images." Photogrammetric Engineering & Remote Sensing 84.8 (2018): 505-512.

  1. From the Toolbox, select Mobility > Forest Cover Classification. The Forest Cover Classification dialog appears.

  2. Select a multispectral or hyperspectral reflectance Input Raster and perform optional spatial or spectral subsetting and/or masking, then click OK. For spectral subsetting, you must retain the red band and either a red edge or NIR band.

    Note: You can generate a reflectance image using the Atmospheric Correction Module.

  3. Use the slider bar or field to specify the value to use for the Max Forest Cover Index. Lower values are more restrictive, resulting in fewer pixels being classified as forest cover.

  4. Select Yes or No for Apply Vegetation Threshold, based on the NDVI value of the pixel.
  5. If Apply Vegetation Threshold is Yes, use the slider bar or field to specify the Min Vegetation Index. Higher values are more restrictive, resulting in fewer pixels being classified as forest cover.

  6. Select whether to Apply Sieving to the classification.

  7. Select whether to Apply Clumping to the classification.

  8. Select the Forest Class Color to use from the color picker.

  9. Enter a filename and location for the Output Raster.
  10. Enable the Preview check box to preview the settings before processing the data. The preview is calculated only on the area in the view and uses the resolution level at which you are viewing the image. To preview a different area in your image, pan and zoom to the area of interest and re-enable the Preview option. Depending on the algorithm being used by the tool, the preview result might be different from the final result of processing on the full extent, full resolution of the input image in the following scenarios: 1) If you zoomed out of the input raster in the view by 50%, or a percentage less than 50%, ENVI uses a downsampled image at the closest resolution level to calculate the preview, or 2) If the entire image is not visible in the view, ENVI uses the subset in the viewable area of the input image to calculate the preview.

  11. Enable the Display result check box to display the output in the view when processing is complete. Otherwise, if the check box is disabled, the result can be loaded from the Data Manager.

  12. To run the process in the background, click the down arrow next to the OK button and select Run Task in the Background. If an ENVI Server has been set up on the network, the Run Task on remote ENVI Server name is also available. The ENVI Server Job Console will show the progress of the job and will provide a link to display the result when processing is complete. See ENVI Servers for more information.

  13. Click OK.

See Also

Mobility Tools