Perform radiometric calibration of SAR images. Following sensors are supported: TerraSAR-X, Sentinel1 and Radarsat-2.Both Single Look Complex(SLC) and detected products are supported as input.


The objective of SAR calibration is to provide imagery in which the pixel values can be directly related to the radar backscatter of the scene. This application allows computing Sigma Naught (Radiometric Calibration) for TerraSAR-X, Sentinel1 L1 and Radarsat-2 sensors. Metadata are automatically retrieved from image products.The application supports complex and non-complex images (SLC or detected products).

This application has several output images and supports “multi-writing”. Instead of computing and writing each image independently, the streamed image blocks are written in a synchronous way for each output. The output images will be computed strip by strip, using the available RAM to compute the strip size, and a user defined streaming mode can be specified using the streaming extended filenames (type, mode and value). Note that multi-writing can be disabled using the multi-write extended filename option: &multiwrite=false, in this case the output images will be written one by one. Note that multi-writing is not supported for MPI writers.


Input Image -in image Mandatory
Input complex image

Output Image -out image [dtype] Mandatory
Output calibrated image. This image contains the backscatter (sigmaNought) of the input image.

Disable Noise -noise bool Default value: false
Flag to disable noise. For 5.2.0 release, the noise values are only read by TerraSARX product.

Lookup table -lut [sigma|beta|gamma|dn] Default value: sigma
Lookup table values are not available with all SAR products. Products that provide lookup table with metadata are: Sentinel1, Radarsat2.

  • Use sigma nought lookup
    Use Sigma nought lookup value from product metadata
  • Use beta nought lookup
    Use Beta nought lookup value from product metadata
  • Use gamma nought lookup
    Use Gamma nought lookup value from product metadata
  • Use DN value lookup
    Use DN value lookup value from product metadata

Available RAM (MB) -ram int Default value: 256
Available memory for processing (in MB).


From the command-line:

otbcli_SARCalibration -in RSAT_imagery_HH.tif -out SarRadiometricCalibration.tif

From Python:

import otbApplication

app = otbApplication.Registry.CreateApplication("SARCalibration")

app.SetParameterString("in", "RSAT_imagery_HH.tif")
app.SetParameterString("out", "SarRadiometricCalibration.tif")