The Resample Library Spectra tool resamples input library spectra to match the number of bands and wavelength range of target spectra from a target sensor, custom spectral library file, or custom image.
The output is an Esri spectral library (.esl) file.
Usage notes
Resample Library Spectra includes configurations for the input layer, resampling settings, and result layer.
Input layer
The Input layer group includes the Input library spectra parameter, which specifies the file containing the spectra that will be resampled. The input library spectra must be an Esri spectral library (.esl) file.
Resampling settings
The Resampling settings group includes the following parameters:
- Target sensor specifies the target sensor, custom spectral library file, or custom image that contains the target spectra.
- Landsat 9—Use Landsat 9 satellite data with 7 bands for the target spectra.
- Landsat 8—Use Landsat 8 satellite data with 7 bands for the target spectra.
- Landsat 7 (No thermal)—Use Landsat 7 satellite data with 6 bands for the target spectra.
- Landsat 5 (No thermal)—Use Landsat 5 satellite data with 6 bands for the target spectra.
- Landsat 4 (No thermal)—Use Landsat 4 satellite data with 6 bands for the target spectra.
- Sentinel-3—Use Sentinel-3 satellite data with 21 bands for the target spectra.
- Sentinel-2A—Use Sentinel-2A satellite data with 13 bands for the target spectra.
- Sentinel-2B—Use Sentinel-2B satellite data with 13 bands for the target spectra.
- ASTER bands 1-9—Use ASTER satellite data with 10 bands for the target spectra.
- Custom target image or spectra (default)—Use a custom spectral library (.esl) file or image that contains the target spectra.
- Custom target image or spectra specifies the spectral library (.esl) file or image that contains the target spectra. To use an .esl file, click Spectra and click Select item, and locate the file in your organization. To use an image, click Image, click Layer, and locate the imagery layer in your organization. If you use an image for the target spectra, it must contain wavelength information.
- Resampling method specifies the resampling method used to resample the input spectral library file. Resampling is performed on wavelengths that overlap between the input spectra and target spectra. The following options are available:
- Band averaging (default)—Calculates the average of the input spectra using band values within each target band's wavelength range. An input band is included in the calculation if its center wavelength falls within the target band's minimum and maximum wavelength range.
- Gaussian convolution—Uses a Gaussian model to represent the spectral response function of the sensor. The input band values are weighted for each wavelength range. An input band is included in the calculation if its center wavelength falls within 3 sigma of the target band's center wavelength, in which sigma is defined as follows:
Result layer
The Result layer group includes the following parameters:
- Output library spectra specifies the name of the Esri spectral library (.esl) file created. The name must be unique. If a file with the same name already exists in your organization, the tool will fail, and you will be prompted to use a different name.
- Save in folder specifies the name of a folder in My content where the result will be saved.
Limitations
The following limitations apply to the tool:
- If the input spectra has a greater wavelength range than the target spectra, the excess bands are discarded in the output spectra.
- If the target spectra has a greater wavelength range than the input spectra, the bands outside of the input spectra are designated with a negative value that you can define as NoData.
Environments
This tool does not honor analysis environments.
Credits
This tool consumes credits.
Use Estimate credits to calculate the number of credits that will be required to run the tool. For more information, see Understand credits for spatial analysis.
Outputs
The output is an Esri spectral library (.esl) file that contains the resampled spectra. The output spectra has the same number of bands and wavelength range as the target spectra.
Licensing requirements
This tool requires the following user type and configurations:
- Creator, Professional, or Professional Plus user type
- Publisher, Facilitator, or Administrator role, or an equivalent custom role
Resources
Use the following resources to learn more:
- Resample Library Spectra in ArcGIS API for Python
- Resample Library Spectra in ArcGIS Pro