GAMMA Interferometric Point Target Analysis Software (IPTA): Reference Manual

prox_pt

ANSI-C program: prox_pt.c

NAME
prox_pt - generate point list of elements in an existing point list which are close to a particular location

SYNOPSIS
prox_pt <plist_in> <pmask> <cr> <cl> <dr> <dl> <np_max> <plist_out>

<plist_in>	(input) point list (int)
<pmask>	(input) point data stack of mask values (uchar, set to - to accept all points)
<cr>	area center range coordinate
<cl>	area center azimuth line number
<dr>	area range search width (cr-dr,cr+dr), enter - for the entire image width
<dl>	area azimuth line number search window (cl-dl,cl+dl), enter - for all lines
<np_max>	maximum number of nearest points to include, enter - for all
<plist_out>	(output) point list of nearest points in indicated area (int)

EXAMPLE
prox_pt testsite.plist testsite.pmask 214 712 50 250 20 testsite.plist1

Reads the input point list and generates a small point list of points near coordinate (214,712) with maximum 20 points.

prox_pt testsite.plist - 214 712 - - 20 testsite.plist2

Reads the input point list and generates a small point list of the 20 nearest points of coordinate (214,712).

prox_pt testsite.plist testsite.pmask 214 712 50 250 - testsite.plist3

Reads the input point list and generates a small point list of all points within the indicated range pixels (50) and azimuth lines (250) of coordinate (214,712).

INSTALLATION
Source code prox_pt.c in ./IPTA/src, executable version prox_pt in ./IPTA/bin

DESCRIPTION
For an existing point list prox_pt generates a new point list of those valid points which are located close to an indicated coordinate.

For the center of the search the range and azimuth coordinate (relative to the reference SLC geometry) are indicated. The search area can further be limited by indicating a mask file and maximum distances in range pixels and azimuth lines.

prox_pt searches all valid points of the input point list in the indicated search area, orders these by increasing distance from the area center, and writes out the nearest points up to the indicated maximum number.

Point lists for small areas are of interest for a detail analysis, for example in the vicinity of targets of interest (a factory, a house, a bridge, a dam, a mine, a construction site, ...).

Other programs to generate new point lists are image2pt, merge_pt, mkgrid, pwr_stat, and sp_stat.

Programs to validate existing point lists are qc_pt and expand_pt.

OPTIONS
none.