i.histo.match - GRASS GIS manual

NAME

i.histo.match - Calculate histogram matching of several images.

KEYWORDS

SYNOPSIS

i.histo.match

i.histo.match --help

i.histo.match input=name[,name,...] [suffix=string] [output=name] [database=name] [max=integer] [--overwrite] [--help] [--verbose] [--quiet] [--ui]

Flags:

--overwrite: Allow output files to overwrite existing files
--help: Print usage summary
--verbose: Verbose module output
--quiet: Quiet module output
--ui: Force launching GUI dialog

Parameters:

input=name[,name,...] [required]: Name of raster maps to be analyzed
suffix=string: Suffix for output maps; Default: match
output=name: Name for mosaic output map
database=name: Name of database; Default: $GISDBASE/$LOCATION_NAME/$MAPSET/histo.db
max=integer: Number of the maximum value for raster maps; Default: 255

DESCRIPTION
NOTES
EXAMPLE
SEE ALSO
AUTHORS

DESCRIPTION

i.histo.match performs histogram matching on the given input images.

The histogram matching method is based on the method Cumulative Distribution Function (CDF) of two or more histograms. Each value of original CDF is compared with the target histogram in order to obtain the target CDF value closest to the original value.

EXAMPLE

This example is based the North Carolina GRASS sample data set, [complete GRASS location].

# create the output with histogram matching
i.histo.match input=lsat5_1987_10,lsat7_2000_10

# set grey color to the new maps
r.colors map=lsat5_1987_10.match color=grey
r.colors map=lsat7_2000_10.match color=grey

# visualize and compare the results

Original data:

Matched data:

AUTHORS

Luca Delucchi, Fondazione E. Mach (Italy)

based on original PERL code was developed by: Laura Zampa (2004), student of Dipartimento di Informatica e Telecomunicazioni, Facolta' di Ingegneria, University of Trento and ITC-irst, Trento (Italy)

SOURCE CODE

Available at: i.histo.match source code (history)