i.gcp - GRASS GIS manual

Note: This addon document is for an older version of GRASS GIS that will be discontinued soon. You should upgrade your GRASS GIS installation, and read the current addon manual page.

NAME

i.gcp - Manages Ground Control Points (GCPs) non-interactively.

KEYWORDS

imagery, georectification, GCP

SYNOPSIS

i.gcp

i.gcp --help

i.gcp [-lcduibrLB] group=name [image_coordinates=east,north] [target_coordinates=east,north] [status=string] [point=integer[,integer,...]] [--help] [--verbose] [--quiet] [--ui]

Flags:

-l: List all ground control points
-c: Clear all ground control points
-d: Delete selected ground control points
-u: Use selected ground control points
-i: Ignore selected ground control points
-b: Back up the point file
-r: Restore the backup point file
-L: List all ground control points in the backup point file
-B: Remove the backup point file
--help: Print usage summary
--verbose: Verbose module output
--quiet: Quiet module output
--ui: Force launching GUI dialog

Parameters:

group=name [required]: Name of input imagery group
image_coordinates=east,north: Image coordinates to add
target_coordinates=east,north: Target coordinates to add
status=string: Status for new ground control points; Options: use, ignore; Default: use
point=integer[,integer,...]: Point number(s) to manage; Options: 1-

DESCRIPTION
NOTES
EXAMPLES
SEE ALSO
AUTHOR

DESCRIPTION

i.gcp manages Ground Control Points (GCPs) non-interactively.

NOTES

Unlike g.gui.gcp, i.gcp can be invoked from the command line or scripts to manage GCPs. It is recommended to create a backup copy of the original POINTS file using -b before making changes to the file. The backup POINTS file (POINTS_BAK) can be restored using -r or removed later using -B. GCPs in the backup POINTS file can be listed using -L.

EXAMPLES

List all GCPs in group "sar":

i.gcp -l group=sar

Create a backup copy of the current POINTS file:

i.gcp -b group=sar

Clear all GCPs first by removing the POINTS file:

i.gcp -c group=sar

Add new GCPs at the bottom-left and top-right corners of the satellite imagery:

i.gcp group=sar image_coordinates=0,0,31996,32239 target_coordinates=493920,3880490,529470,3916310

Add another GCP that will be ignored for now and list all GCPs:

i.gcp -l group=sar image_coordinates=100,100 target_coordinates=500000,4000000 status=ignore

Use the GCP just added and list all:

i.gcp -u -l group=sar point=3

Delete point 1:

i.gcp -d -l group=sar point=1

Ignore points 1-2:

i.gcp -i -l group=sar point=1-2

List GCPs in the backup POINTS file:

i.gcp -L group=sar

Restore the backup POINTS file:

i.gcp -r group=sar

Remove the backup POINTS file:

i.gcp -B group=sar

AUTHOR

Huidae Cho

SOURCE CODE

Available at: i.gcp source code (history)

Latest change: Mon Jun 28 07:54:09 2021 in commit: 1cfc0af029a35a5d6c7dae5ca7204d0eb85dbc55