Summary
Calculates the Iron Oxide (IO) ratio from a multiband raster object and returns a raster object with the index values.
Discussion
The iron oxide ratio is a ratio of the red and blue wavelengths. The presence of limonitic-bearing phyllosilicates and limonitic iron oxide alteration cause absorption in blue band and reflectance in red band. This causes areas with strong iron alteration to be bright. The nature of the ratio allows this index to mitigate illumination differences caused by terrain shadowing.
Iron Oxide Ratio = Red / Blue
- Red = pixel values from the red band
- Blue = pixel values from the blue 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
IronOxide (raster, {red_band_id}, {blue_band_id})
Parameter | Explanation | Data Type |
raster | The input raster. | Raster |
red_band_id | The band ID of the red band. The ID index uses one-based indexing. (The default value is 4) | Integer |
blue_band_id | The band ID of the blue band. The ID index uses one-based indexing. (The default value is 2) | Integer |
Data Type | Explanation |
Raster | The output raster object with the Iron Oxide ratio values. |
Code sample
Calculates the Iron Oxide ratio for a Sentinel-2 image.
import arcpy
IronOxide_raster = arcpy.ia.IronOxide("Sentinel2.tif", 4, 2)