ANSI-C program: coord_to_sarpix.c
NAME
coord_to_sarpix - Calculate SAR pixel coordinates (iazpix,jrpix)
of geographic coordinate.
SYNOPSIS
coord_to_sarpix <SLC_par> <interf_par>
<DEM_par> <north/lat> <east/lon> <hgt>
[DIFF_par]
| <SLC_par> | (input) ISP SLC/MLI parameter file |
| <OFF_par> | (input) ISP offset/interferogram parameter file, enter - for SLC or MLI data |
| <DEM_par> | (input) DEM parameter file, enter - for WGS84 lat/lon |
| <north/lat> | northing (m) or latitude (deg.) |
| <east/lon> | easting (m) or longitude in (deg.) |
| <hgt> | (input) reference height (m) in map datum |
| [DIFF_par] |
[input] DIFF/GEO parameter
file containing refinement polynomial coefficients |
EXAMPLE
coord_to_sarpix 19990915.slc.par -
utm.dem_par 6245990 160350 600.0
Calculates the corresponding SAR MLI image pixel number and
writes it to standard output (azimuth/row, slant range/col).
The dimensions and resolution of the image in SAR range-doppler
coordiantes (RDC) are obtained from the
ISP image parameter file (SLC_par).
coord_to_sarpix 19990915.slc.par - utm.dem_par 6245990
160350 600.0 19990915.diff_par
Calculates the corresponding SAR MLI image pixel number and
writes it to standard output (azimuth/row, slant range/col).
The dimensions and resolution of the image in SAR range-doppler
coordiantes (RDC) are obtained from the ISP image parameter
file. The DIFF_par contains offset polynomials derived
during geocoding of the image. These offset polynomials are used
to adjust the SLC pixel coordinates for errors in the state
vectors and azimuth timing.
coord_to_sarpix 19990915 .slc.par - - 17. -114.
600.0
Calculates the corresponding SAR image pixel number and writes
it to standard output (azimuth/row, slant range/col). The input
coordinates are geographic coordinates lat/long in
WGS84.
DESCRIPTION
coord_to_sarpix
calculates for an indicated map coordinate the corresponding
slant range and azimuth pixel numbers in the SAR range-Doppler
geometry defined by the indicated parameter file. If the
DEM parameter file is entered, then the point coordinates in map
coordinates are in the projection defined in the DEM parameter
file. If no DEM parameter file is specified, the command line
input coordinates are assumed to be latitude and longitude in
decimal degrees with a WGS84 reference ellipsoid,
The SAR image geometry is defined by the ISP image parameter
file. If an additional ISP OFF_par is specified, then the
image parameters will be taken from the OFF_par. In the
current use of the Gamma software, interferograms and MLI image
products typically cover the
same areas as specified in the SLC/MLI par file and the OFF_par
can be ommitted.
Pixel numbers outside the SAR image or interferogram are
valid, including negative pixel numbers. These indicate that the
point specified in map coordinates lies outside the given SAR
image.
If the DIFF_par is provided on the command line, the geocoding
offset polynomials that are contained in the parameter file
after scene geocoding can be used to remove residual errors in
the pixel coordinates due to state vector and timing
errors.
The supported DEM projections are :
| EQA | Equiangular geographical coordinates (degrees lat/lon) |
| UTM | Universal Transverse Mercator Projection |
| TM | Transverse Mercator Projection |
| OM | Oblique Mercator |
| OMCH | Oblique Mercator (Switzerland) |
| HOM | Hotine Oblique Mercator |
| LCC | Lambert Conformal Conic (France) |
| LCC2 | Lambert Conformal Conic Projection of Belgium, Madagascar |
| PS | Polar Stereographic Projection |
| SCH | SAR Coordinates used at JPL |
| PC | Polyconic Projection |
| AEAC | Albers Equal Area Conic |
A new DEM/map geometry can be defined using the program create_dem_par.
The transformation of coordinates between different map projections is supported by the program coord_trans.
The inverse transformation (SAR image pixel number to map coordinate) is supported by the program sarpix_coord.
SEE ALSO
coord_trans, sarpix_coord, create_dem_par, datums.h, ellipsoids.h, projection_params.h, typedef_ISP.h, typedef_DIFF.h .