Extract Spectra From Image (Image Analyst Tools)

Summary

Extracts spectral signatures from input feature data to create an Esri Spectral Library (.esl) file. The reference spectral data may be collected from the field, such as GPS data, in the form of point feature or polygon features. These features record the locations of the materials of interest, or class types.

You may also extract spectra data from the training sample feature class. This provides a way to create a spectral library from the image and the location feature class.

Usage

Use reference spectral data collected in the field that records the locations of the interested materials or class types.
Use reference spectral data collected from a target image that records the locations of the interested materials or class types. This feature data is collected using the Training Sample Manager.
The reference spectral data can be point features or polygon features.

Label	Explanation	Data type
Input Raster	A multispectral or hyperspectral image that contains wavelength information.	Raster Dataset; Mosaic Dataset; Mosaic Layer; Raster Layer; Image Service; File; String
Input Location Feature Class	A point or polygon feature class that defines the locations of the target materials. If the location features are polygons, an average spectra will be created for each polygon and each material type.	Feature Class
Material Name Field	A field that identifies the material name, such as class name.	Field
Output Spectral Library	An output spectral library file that stores the extracted spectral signatures.	File

ExtractSpectraFromImage(in_raster, in_feature, material_field, out_spectra)

Name	Explanation	Data type
in_raster	A multispectral or hyperspectral image that contains wavelength information.	Raster Dataset; Mosaic Dataset; Mosaic Layer; Raster Layer; Image Service; File; String
in_feature	A point or polygon feature class that defines the locations of the target materials. If the location features are polygons, an average spectra will be created for each polygon and each material type.	Feature Class
material_field	A field that identifies the material name, such as class name.	Field
out_spectra	An output spectral library file that stores the extracted spectral signatures.	File

Code sample

ExtractSpectraFromImage example 1 (Python window)

Extract spectral signatures from input feature data and outputs an Esri Spectral Library (.esl) file.

# Import system modules
import arcpy
from arcpy.ia import *

# Run ExtractSpectraFromImage
arcpy.ia.ExtractSpectraFromImage(r"c:\data\hsi_image.tif", r"c:\data\location.shp", "material_type",  r"c:\data\my_spectra.esl")

ExtractSpectraFromImage example 2 (stand-alone script)

Extract spectral signatures from input feature data and outputs an Esri Spectral Library (.esl) file.

# Import system modules
import arcpy
from arcpy.ia import *

# Define variables
input_image = r"c:\data\hsi_image.tif"
input_location = r"c:\data\location.shp"
output_library = r"c:\data\my_spectra.esl"
material_field_name = "material_type"

# Run ExtractSpectraFromImage
arcpy.ia.ExtractSpectraFromImage(input_image, input_location, material_field_name, output_library)

Environments

Extent, Geographic Transformations, Output Coordinate System

Licensing information