ANSI-C program: ph_base_pt.c
NAME
ph_base_pt - subtract/add interferogram flat-Earth phase trend
(single record or all records)
SYNOPSIS
ph_base_pt <plist> <pmask> <pSLC_par>
<ppos> <itab> <rec_num> <pbase>
<pint> <pflt> [int_type] [inverse]
| <plist> | (input) point list (int) |
| <pmask> | (input) point data stack of mask values (uchar, set to - to accept all points) |
| <pSLC_par> | (input) stack of SLC/MLI parameters (binary) |
| <ppos> | (input) point data stack of interpolated point target position (fcomplex, enter - to use plist coordinates) |
| <itab> | (input) table associating interferogram stack records
with pairs of SLC stack records (ascii) (line entries are: pSLC_rec1 pSLC_rec2 itab_rec_num switch_flag) |
| <rec_num> | record number to process (default -: all records) |
| <pbase> | (input) stack of baseline parameters (binary) |
| <pint> | (input) point data stack of interferograms (fcomplex or float) |
| <pflt> | (output) point data stack of interferograms with range phase trend subtracted/added (same type as pint) |
| [int_type] | type of pint and pflt (0: float(i.e. unwrapped phase), default=1: fcomplex) |
| [inverse] | subtract/add flag (default=0: subtract phase ramp, 1: add phase ramp) |
EXAMPLE
ph_base_pt testsite.plist testsite.pmask testsite.ppar
testsite.ppos testsite.itab 3 testsite.pbase testsite.pint
testsite.pflt 1 0
Subtracts flat Earth phase trend from the interferogram in record 3 of the point data stack of interferograms and writes it out the stack of "flattened" interferograms. For the calculation of the flat Earth phases the interpolated (real valued) point coordinates are used.
Subtracts flat Earth phase trend for all records in the point data stack of interferograms and writes out the "flattened" interferograms to the output point data stack. For the calculation of the flat Earth phases the integer coordinates as provided in the point list are used.
INSTALLATION
Source code ph_base_pt.c in ./IPTA/src, executable version
ph_base_pt in ./IPTA/bin
DESCRIPTION
ph_base_pt subtracts or adds the flat Earth phase trend for
interferograms in point data format. This can be done for complex
valued interferograms or unwrapped (real valued) interferograms
and for a sinlge record of the stack of interferograms or all
records.
The coordinates of the points considered are defined in the point list. The optional mask file indicates for each point if it is valid (1, i.e. considered) or not volid (0, excluded).
The itab is a text file which associates the interferogram stack records with pairs of SLC stack records. For each interferogram stack record the itab contains a line with the SLC stack record number of the master SLC, the SLC stack record number of the slave SLC, the interferogram stack record number of the interferogram, and a flag (1 or 0) to switch a record on or off (i.e. to consider or exclude a record when processing all records).
The SLC parameter files of the master SLC which are used to calculate the flat Earth phases are provided in the stack of SLC/MLI parameters. Optionally, integrated point target positions may be provided in a point data stack of interpolated point target positions. If not provided, the integer valued coordinates of the point list are used.
The baseline parameters (initial baseline is used) which are required to calculate the flat Earth phases are provided in the stack of baseline parameters.
The input interferograms are provided as a point data stack. This stack is of fcomplex type for complex valued interferograms and of float type for unwrapped interferometric phase images. The type of the output stack of "flattened" interferograms is of the same type as the input stack.
The "flattened" interferogram (or more generally speaking the output interferogram) is calculated for each valid point of the point list. Valid points are points with a non-zero input interferogram value and a non-zero mask value (if provided). For each valid point the flat Earth phase is calculated. This phase is either subtracted from the input interferograms ("flattening") or added to the input interferogram ("reramping").
If a new output stack name is indicated the stack is created. Indicating a record number larger than the highest record number of the indicated stack results in an increase of the stack size.
To display the complex or real valued input or output interferograms contained in the point data stack the programs pt2data or pt2d can be used to convert the point data to raster data format which can then be displayed using conventional display programs.
OPTIONS
none.
SEE ALSO
pt2data, pt2d,
ipta.h.
© Copyrights for Documentation, Users Guide and Reference Manual by Gamma Remote Sensing, 2003.
UW, CW, TS, last change 20-Feb-2003.