Summary
Calculates the Normalized Burn Ratio (NBR) from a multiband raster object and returns a raster object with the index values.
Discussion
The Normalized Burn Ratio Index (NBRI) uses the NIR and SWIR bands to emphasize burned areas, while mitigating illumination and atmospheric effects. Your images should be corrected to reflectance values before using this index; see the Apparent Reflectance function for more details.
NBR = (NIR - SWIR) / (NIR+ SWIR)
- NIR = pixel values from the near infrared band
- SWIR = pixel values from the short-wave infrared band
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
NBR (raster, {swir_band_id}, {nir_band_id})
Parameter | Explanation | Data Type |
raster | The input raster. | Raster |
swir_band_id | The band ID of the shortwave infrared band. The ID index uses one-based indexing. (The default value is 7) | Integer |
nir_band_id | The band ID of the near-infrared band. The ID index uses one-based indexing. (The default value is 5) | Integer |
Data Type | Explanation |
Raster | The output raster object with the NBR values. |
Code sample
Calculates the Normalized Burn Ratio for a Landsat 8 image.
import arcpy
NBR_raster = arcpy.ia.NBR("Landsat8.tif", swir_band_id = 7, nir_band_id = 5)
Calculates the Normalized Burn Ratio for a Landsat 8 image.
# Import system modules
import arcpy
from arcpy.ia import *
# Set the analysis environments
arcpy.env.workspace = "C:/arcpyExamples/data"
# Set the local variables
in_raster = "landsat8.tif"
# Execute NBR function
out_nbr_raster = NBR(in_raster, 7, 5)
# Save the output
out_nbr_raster.save("C:/arcpyExamples/outputs/NBR.tif")