Single Image Workflow

Purpose

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

–Import SAR Data

–Sample Selection SAR Geometry Data

–Multilooking.

–Coregistration.

–De Grandi Multi-temporal Filtering.

–Geocoding and Radiometric Calibration.

–Multi Temporal Features.

The final purpose of this processing chain is to enable the generation of terrain geocoded sigma nought data.

Technical Note

Details specific to each step implemented here are described in their respective reference guide section. We recommend to read them carefully.

Note: this workflow allows importing and subsampling SAR data. In case SAR Data have already been imported and subsampled, these unnecessary steps will be skipped by setting to True these steps in the Input step - Parameters tab.

Input

Input Files

Area of Interest

In case of SLC IW import, a vector file (.shp), or a Google Earth file (.kml or .kmz) can be upload to specify a region of interest. Only the bursts intersecting this region will be imported. This will reduce the import processing time and 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 List

Input file name(s) of the Single Look Complex (_slc), slant range (_pwr) or ground range (_gr) Intensity data. This file list is mandatory.

DEM/Cartographic System

Reference Type

The choice is given between the three following options:

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

•Reference Height: in case that the Digital Elevation Model is not used, the parameters needed to define the Cartographic System, the pixel spacing and the reference height are compulsory;

•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 that the choice of one source is compulsory.

Parameters

•Skip Import SAR Data: it allows skipping the Import SAR Data step if set to True in case these data have already been imported;

•Skip Sample Selection : it allows skipping the Sample Selection SAR Geometry Data, if set to True, in case these data have already been sampled and the _cut files have already been created;

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.

Mean

By setting this flag the output pixel value represents the average calculated from all input data.

Span Difference

By setting this flag the output pixel represents the difference between the maximum value and the minimum value of all input data.

Coefficient of Variation

By setting this flag the output pixel represents the standard deviation/mean ratio.

Min

By setting this flag the output pixel represents the minimum value extracted from all input data.

Max

By setting this flag the output pixel represents the maximum value extracted from all input data.

Import 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.

Sample Selection SAR

It allows subsampling a spatial subset to be extracted from a single image or from an image stack. For more details refer to the sample selection in SAR geometry.

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.

Coregistration

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

De Grandi Multi-temporal Filtering

It brings to the principal parameters of the De Grandi Multi-temporal Filtering step. Refer to the relevant section technical note for further information about the process and other Preferences parameters.

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.

Multi Temporal Features

It brings to the principal parameters of the Multi Temporal Features step. Refer to the relevant section technical note for further information about the process and other Preferences parameters. Note: Most used Multi Temporal Featues can be set in the proper preference tab in SARscape preferences.

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.

_spanD

Span difference and associated header files (.sml, .hdr).

_spanR

Span ratio and associated header files (.sml, .hdr).

_cov

Coefficient of variation and corresponding header files (.sml, .hdr).

_mea

Mean image and associated header files (.sml, .hdr).

_med

Median image and associated header files (.sml, .hdr).

_max

Maximum value and associated header files (.sml, .hdr).

_min

Minimum value and associated header files (.sml, .hdr).

muSigma

MuSigma value and associated header files (.sml, .hdr).

_maxD

Maximum decrement and associated header files (.sml, .hdr).

_maxI

Maximum increment and associated header files (.sml, .hdr).

_maxR

Maximum ratio and associated header files (.sml, .hdr).

_minR

Minimum ratio and associated header files (.sml, .hdr).

_std

Standard deviation and associated header files (.sml, .hdr).

_CovMin_grad_rgb.tif

TIFF image of the assembled RGB imageand associated header files (.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 - Single Image Workflow

Basic Module - Single Image Workflow