Zusammenfassung
Calculates the Visible Atmospherically Resistant Index (VARI) from a multiband raster object and returns a raster object with the index values.
Diskussion
Die Methode "Visible Atmospherically Resistant Index (VARI)" ist ein Vegetationsindex. Sie dient zur quantitativen Schätzung des Vegetationsanteils, der ausschließlich anhand des sichtbaren Anteils des Spektrums bestimmt wird.
VARI = (Green - Red) / (Green + Red – Blue)For information about other multiband raster indexes, see the Band Arithmetic raster function.
The referenced raster dataset for the raster object is temporary. To make it permanent, you can call the raster object's save method.
Syntax
VARI (raster, {red_band_id}, {green_band_id}, {blue_band_id})| Parameter | Erläuterung | Datentyp |
raster | The input raster. | Raster |
red_band_id | The band ID of the red-edge band. The band ID index uses one-based indexing. (Der Standardwert ist 3) | Integer |
green_band_id | The band ID of the green band. The ID index uses one-based indexing. (Der Standardwert ist 2) | Integer |
blue_band_id | The band ID of the blue band. The ID index uses one-based indexing. (Der Standardwert ist 1) | Integer |
| Datentyp | Erläuterung |
| Raster | The output raster with the VARI values. |
Codebeispiel
Calculates the Visible Atmospherically Resistant Index for a Landsat 8 image.
import arcpy
VARI_raster = arcpy.ia.VARI("Landsat8.tif",4,3,2)