Use Georeference Data to georeference SPOT data based on header information. ENVI performs a precision geocoding of the SPOT image using a complete geometry model of the earth and satellite orbit.

  1. Open a SPOT file by selecting File > Open As > Optical Sensors > SPOT >data_type from the menu bar.
  2. Select Geometric Correction > Georeference by Sensor > Georeference SPOT from the Toolbox. The Input SPOT image dialog appears.
  3. Select the SPOT image file.
  4. Click OK. The Georeference SPOT Data dialog appears.
  5. Select the desired output map projection by selecting a projection type from the list. By default, a UTM map projection is selected based on header information.
  6. Enter an optional Avg Scene Elevation (Meters) value.

  7. Enter the Number Warp Points for X and Y. You may select a number of warp points up to the number of samples and lines in your image. If you select fewer warp points, they will be evenly spaced throughout the image.

    To save the warp points to a GCP file, enter or choose an output filename.

    Note: Using a large number of warp points will increase the processing time considerably.

  8. Click OK. The Registration Parameters dialog appears.
  9. Select the warping and resampling methods and change the output dimensions, if desired. The triangulation method is recommended to produce the most accurate results. Note, however, that it will be much slower than polynomial warping.
  10. Enter or choose an output filename.
  11. Click OK.