Summary
Calculates the Normalized Difference Vegetation Index (NDVI) from a multiband raster object and returns a raster object with the index values.
Discussion
The normalized difference vegetation index (NDVI) is a standardized index allowing you to generate an image displaying greenness, also known as relative biomass. This index takes advantage of the contrast of characteristics between two bands from a multispectral raster dataset—the chlorophyll pigment absorption in the red band and the high reflectivity of plant material in the near-infrared (NIR) band.
NDVI = ((NIR - R)/(NIR + R))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
NDVI (raster, {nir_band_id}, {red_band_id})| Parameter | Explanation | Data Type |
raster | The input raster. | Raster |
nir_band_id | The band ID of the near-infrared band. The ID index uses one-based indexing. (The default value is 4) | Integer |
red_band_id | The band ID of the red band. The ID index uses one-based indexing. (The default value is 3) | Integer |
| Data Type | Explanation |
| Raster | The output raster object with the NDVI index values. |
Code sample
Calculates the Normalized Difference Vegetation Index for a Landsat 8 image.
import arcpy
NDVI_raster = arcpy.sa.NDVI("Landsat8.tif", 5, 4)