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<< Click to Display Table of Contents >> Basic Module - Moving Target Detection Workflow |
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This functionality enables to execute, in a single iteration, the following processing sequence:
–Sample Selection SAR Geometry Data
–De Grandi Spatio Temporal filter
–Geocoding and Radiometric Calibration
Objects which are moving in azimuth direction are displayed as unfocused lines in (high resolution) SAR SLC images. This tool allows to detect these moving targets by performing the following steps:
•Split in 3 sub-apertures in azimuth direction.
•Conversion of the sub-apertures SLC in PWR (intensity). The 3 sub-apertures correspond to different antenna squint.
•Creation of an RGB composite using the three resulting _pwr
Thanks to this, moving targets in azimuth direction are highlighted with a complete color spectrum ranging from Red to Green to Blue along the unfocused line.
Distribute and stable targets are showed with an uniform grey coulor (speckle effect apart).
The last step, Generate Color Composite, will create an RGB using the splitted _pwr.
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 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
File name of the input data (_slc). This file 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.
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.
Moving Target Detection
It brings to the principal parameters of the Moving Target Detection 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.
Generate Color Composite
It brings to the principal parameters of the Color Composite Generation step. Refer to the relevant section technical note for further information about the process and other Preferences parameters.
Output
Output file
Output file name of the geocoded RGB file. This file list 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.
..._0_pwr
Intensity of the first split.
..._1_pwr
Intensity of the second split.
..._2_pwr
Intensity of the third split.
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.
Close
The window will be closed.
References
Consult the reference guide specific to each processing step.