Help Content > Basic Module > Intensity Single Image Workflow

Purpose

This functionality enables to execute, in a single iteration, the following processing sequence:

The final purpose of this processing chain is to enable the generation of geocoded filtered image.

Technical Note

Specific details of each step are described in their respective reference help page. We recommend to read them carefully.

Note: this workflow allows importing and subsampling SAR data. In case SAR data have already been imported, SARscape recognizes the imported file. In case the SAR data have already been subsampled, these unnecessary step is skipped by setting to True the Skip Sample Selection in the Import Generic SAR Data.

Input

Input Files

Area of interest in Geographic Coordinates

A vector file (.shp), or a Google Earth file (.kml or .kmz) can be upload to specify a region of interest.

This input reduces the disk space needs. This file is optional.

Note: Only AOI files in geographic coordinates (Lat/Long) are supported. If the needed shapefile is available only in another cartographic system, please use the Cartographic Transformation Shape tool to convert it in Lat/Long.

Input File (Mandatory)

Input file name of the Single Look Complex (_slc), slant range (_pwr) or ground range (_gr) Intensity data or original data.

DEM/Cartographic System

Reference Type

The choice is given between the two following options:

•Input DEM: the provided "Input Digital Elevation Model" file is used in the process previously imported;

•DEM Download: The Digital Elevation Model Extraction tool is used to download an online digital elevation model. Various sources are available, see this section for further information.

Note: the choice of one source is compulsory.

Parameters

Grid Size

The grid size of the output data must be defined; the default unit of measure is meters.

Note that - for the Geographic projection - if values higher than 0.2 are entered they will be considered as metric units and then automatically, and roughly, converted from meters to degrees; if values lower than 0.2 are entered they will be considered as degree and used as such without any conversion.

Filtering Method

Refer to the relevant section technical note for further information about the process and other Preferences parameters.

Note on Gamma Filters use depends on the license availability.

Note on Non Local: We warmly recommended to use this filter only in combination with a powerful GPU selected as the current OpenCL platform/device under the SARscape Common Preferences.

Import Generic SAR Data

It allows importing generic SAR data. Some parameters refer only to Sentinel-1 data, in this case "SENTINEL" is reported in the specific field to fill out. For more details refer to Import Data Generic SAR data.

Multilooking

It brings to the principal parameters of the Multilooking step. Refer to the relevant section technical note for further information about the process and other Preferences parameters.

Single Image Filtering

It brings to the principal parameters of the Filtering Method step.

Equivalent Number of Looks (ENL)

The Equivalent Number of Looks is equivalent to the number of independent Intensity values averaged per pixel during the multi-looking process. This parameter can be easily estimated over a homogeneous (stationary) sample in the input Intensity data according to:

ENL = mean2 / standard deviation2

In case that ENL is not set, the software tries to retrieve it automatically; if it fails it takes the Number of Looks (NL) used during the multi-looking process is considered.

Note that, to tune the strength of speckle filtering and the level of preservation of scene details, it is preferable to adjust the value of the ENL, rather than to change the size of the processing window:

-To reduce the strength of speckle filtering, with the aim to preserve the thinnest details of the scene, enter a ENL value slightly higher than the calculated one;

-Inversely, to improve the filtering of the speckle (possibly at the cost of the thinnest details of the scene), enter a ENL value slightly lower than the calculated one.

Geocoding and Radiometric Calibration

It brings to the principal parameters of the Geocoding and Radiometric Calibration step. Refer to the relevant section technical note for further information about the process and other Preferences parameters.

Output

Output Root Name

Name of the output root. This file is mandatory.

Delete Temporary Files

By setting this flag, temporary files which are created in the intermediate steps, are automatically removed. All of the intermediate files are kept otherwise, refer to the Output lists relevant to each processing step for further information.

_fil_geo

Filtered image header files (.sml, .hdr).

Details specific to the Units of Measure and Nomenclature of the output products can be found in the Data Format section

General Function(s)

Preview

By setting this flag, the temporary files are made available to visualize after a single step in the chain.

Delete Temporary Files

By setting this flag to false, It is possible to keep all the temporary files created during the processing. The files are located in the ENVI Output Directory in a folder with the following name: SARsTmpDir_ddmmmyyyy_hhmmss

Save

Clicking this button allows to save and close the workflow at the actual step. After saving the workflow the window will be closed

Open

Clicking this button allows to open a previously saved workflow.

< Back

Clicking this button the previous step of the workflow is shown.

Next >

Clicking this button the actual step of the workflow is performed. once finished, the next step is shown.

Next >>>

Clicking this button all the steps are performed in succession and it is no more necessary to use the "Next >" button. Make sure that all settings in all the steps are correctly set before starting with this processing.

The window will be closed.

References

Consult the reference guide specific to each processing step.

Basic Module - Intensity Single Image Workflow

Basic Module - Intensity Single Image Workflow