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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-

Table of contents

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

SEE ALSO

The GRASS 4 Image Processing manual

i.group, i.target, i.rectify, i.points.auto, Ground Control Points Manager

AUTHOR

Huidae Cho

Last changed: $Date: 2016-03-21 07:18:00 +0100 (Mon, 21 Mar 2016) $

SOURCE CODE

Available at: i.gcp source code (history)


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© 2003-2018 GRASS Development Team, GRASS GIS 7.4.2svn Reference Manual