Gamma DIFF&GEO: Reference Manual

sarpix_coord

NAME
sarpix_coord -Transform SAR image coordinates to map projection or geographic (lat/lon) coordinates

SYNOPSIS
sarpix_coord <SLC_par> [OFF_par] [DEM_par] [azlin] [rpix] [ref_hgt]

<SLC_par>	(input) ISP SLC/MLI parameter file
[interf_par]	(input) ISP offset/interferogram parameter file, enter - for SLC or MLI data
[DEM_par]	(input) DEM parameter file, enter - for WGS84 lat/lon
[azlin]	SAR image azimuth line
[rpix]	SAR image slant range pixel number
[ref_hgt]	(input) reference height (m) in map datum

EXAMPLES

sarpix_coord 19990421.slc.par 19990421_19990422.off utm.dem_par 75 1800 600.0

Calculates geographic coordinates in the UTM map projection as defined in the DEM parameter file utm.dem_par. The map coordinates and UTM projection coordinates are calculated for the 4 corners of the interferogram specified by the SLC parameter file 19990421.slc.par and the offset/interferogram parameter file 19990421_19990422.off. The UTM projection coordinates are also calculated for the position specified on the command line (75, 1800). The reference height is specified to be 600 meters.

sarpix_coord 19990421.slc.par - utm.dem_par 75.5 1800.3

Calculates geographic coordinates in the UTM map projection as defined in the DEM parameter file utm.dem_par. The map coordinates and UTM projection coordinates are calculated for the 4 corners of the SLC specified by the SLC parameter file 19990421.slc.par. The UTM projection coordinates are also calculated for the position specified on the command line (75.5, 1800.3). The reference height is the default value of 0.0 meters.

sarpix_coord 19990421.slc.par

Calculates geographic (latitude, longitude) coordinates of the four corners of an SLC image (geometry defined by 19990421.slc.par), using a reference height in the WGS84 datum of 0.0 meter.

DESCRIPTION
sarpix_coord calculates geographic coordinates of a selected pixel of an image in SAR range-Doppler geometry and of the four SAR image corners. The SAR image geometry for an SLC or MLI image is described by the ISP image parameter file.

Only in the case where an interferogram that covers only a subregion of the SLC is the ISP offset-parameter file (OFF_par) required that defines the region boundaries. Coordinates are then relative to the interferogram geometry.

When specifying a location in the SAR image on command line, the coordinates azlin and rpix can be floating point numbers. Pixel numbers outside the SAR image or interferogram are also valid, including negative pixel numbers.

The output map geometry is defined by the DEM parameter file entered on the command line. If no DEM_par is entered, then the map coordinate values will be latitude and longitude for the WGS84 ellipsoid.

A reference height can be provided on the command line. The specified height is in the output map datum.

The transformation of individual coordinates between different map projections is supported by the program coord_trans.