Pre-Processing Related Modules¶

Wrapper function for geocoding SAR images using pyroSAR:

The purpose of the pyroSAR package is to provide a complete solution for the scalable organization and

processing of SAR satellite data:

* Reading of data from various past and present satellite missions

* Handling of acquisition metadata

* User-friendly access to processing utilities in SNAP and GAMMA Remote Sensing software

* Formatting of the preprocessed data for further analysis

class gscpy.pr_geocode.pr_geocode.Geocode(input_dir, outdir, pattern=None, t_srs=None, t_srs_from_file=None, resolution_value=20, polarizations='all', shapefile=None, scaling='dB', geocoding_type='Range-Doppler', removeS1BoderNoise=True, offset=None, external_dem_file=None, external_dem_nan=None, externalDEMApplyEGM=True, basename_extensions=None, test=False, verbose=False)[source]¶

Wrapper function for geocoding SAR images using pyroSAR.

Parameters:

input_dir (str) – Directory where the Sentinel-Data is.
outdir (str) – The directory to write the final files to.
t_srs (int, str or osr.SpatialReference) – A target geographic reference system in WKT, EPSG, PROJ4 or OPENGIS format. See function spatialist.auxil.crsConvert() for details. Default: 4326.
resolution_value (int or float, optional) – The target resolution in meters. Default is 20
polarizations (list or {'VV', 'HH', 'VH', 'HV', 'all'}, optional) – The polarizations to be processed; can be a string for a single polarization e.g. ‘VV’ or a list of several polarizations e.g. [‘VV’, ‘VH’]. Default is ‘all’.
shapefile (str or Vector, optional) – A vector geometry for subsetting the SAR scene to a test site. Default is None.
scaling ({'dB', 'db', 'linear'}, optional) – Should the output be in linear or decibel scaling? Default is ‘dB’.
geocoding_type ({'Range-Doppler', 'SAR simulation cross correlation'}, optional) – The type of geocoding applied; can be either ‘Range-Doppler’ (default) or ‘SAR simulation cross correlation’
removeS1BoderNoise (bool, optional) – Enables removal of S1 GRD border noise (default).
offset (tuple, optional) – A tuple defining offsets for left, right, top and bottom in pixels, e.g. (100, 100, 0, 0); this variable is overridden if a shapefile is defined. Default is None.
external_dem_file (str or None, optional) – The absolute path to an external DEM file. Default is None.
external_dem_nan (int, float or None, optional) – The no data value of the external DEM. If not specified (default) the function will try to read it from the specified external DEM.
externalDEMApplyEGM (bool, optional) – Apply Earth Gravitational Model to external DEM? Default is True.
basename_extensions (list of str) – names of additional parameters to append to the basename, e.g. [‘orbitNumber_rel’]
test (bool, optional) – If set to True the workflow xml file is only written and not executed. Default is False.

files¶: list – All detected files.

geocode()[source]¶: Start the geocoding process.

import_products(pattern=None, mapset=None, dbase=None, location=None, flags=None)[source]¶: Import detected files.

print_products()[source]¶: Print all detected files.

Examples

The general usage is

$ pr.geocode [-e -i -r -l -c -p -t -b] input_dir=string outdir=string [pattern=string] [t_srs=string] [t_srs_from_file=string]
    [resolution_value=integer] [polarizations=string] [shapefile=string] [scaling=string]
    [geocoding_type=string] [offset=string] [external_dem_file=string] [external_dem_nan=integer]
    [basename_extensions=string] [mapset=string] [dbase=string] [location=string] [--verbose] [--quiet]

Import Sentinel 1A files geocode and import them in current mapset and reproject it

$ pr.geocode -r input_dir=/home/user/data outdir=/home/user/data/processed t_srs=43265

Import Sentinel 1A files geocode and import them in a new mapset within another GRASS GIS database

$ pr.geocode -r input_dir=/home/user/data outdir=/home/user/data/processed t_srs=43265 mapset=Goettingen dbase=/home/user/grassdata/germany

Note

If only one polarization is selected the results are directly written to GeoTiff. Otherwise the results are first written to a folder containing ENVI files and then transformed to GeoTiff files (one for each polarization). If GeoTiff would directly be selected as output format for multiple polarizations then a multilayer GeoTiff is written by SNAP which is an unfavorable format

Notes

Flags:

e : Apply Earth Gravitational Model to external DEM.
i : Import processed files in a mapset.
r : Reproject raster data (using r.import if needed).
l : Link raster data instead of importing.
c : Create a new mapset.
p : Print the detected files and exit.
t : Write only the workflow in xml file
b : Enables removal of S1 GRD border noise.

geocode()[source]

Start the geocode process.

Returns:
Return type:	None

import_products(pattern=None, mapset=None, dbase=None, location=None, flags=None)[source]

Import all detected files in a mapset.

Parameters:	pattern (str, optional) – The pattern of file names. If not specified all files with selected extension will be imported. mapset (str, optional) – Name of mapset. dbase (str, optional) – Location of GRASS GIS database mapset – Name of the mapset that will be created. flags (str) – Available flags are ‘-c-r-l’
Returns:
Return type:	None

print_products()[source]

Print all detected files.

Returns:
Return type:	None