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GDAL-RASTER-RGB-TO-PALETTE(1)	      GDAL	   GDAL-RASTER-RGB-TO-PALETTE(1)

NAME
     gdal-raster-rgb-to-palette  -  Convert  a	RGB  image into a pseudo-color /
     paletted image.

     Added in version 3.12.

SYNOPSIS
	Usage: gdal raster rgb-to-palette [OPTIONS] <INPUT> <OUTPUT>

	Convert a RGB image into a pseudo-color / paletted image.

	Positional arguments:
	  -i, --input <INPUT>				       Input raster datasets [required] [not available in pipelines]
	  -o, --output <OUTPUT> 			       Output raster dataset [required] [not available in pipelines]

	Common Options:
	  -h, --help					       Display help message and exit
	  --json-usage					       Display usage as JSON document and exit
	  --config <KEY>=<VALUE>			       Configuration option [may be repeated]
	  -q, --quiet					       Quiet mode (no progress bar or warning message) [not available in pipelines]

	Options:
	  -f, --of, --format, --output-format <OUTPUT-FORMAT>  Output format ("GDALG" allowed) [not available in pipelines]
	  --co, --creation-option <KEY>=<VALUE> 	       Creation option [may be repeated] [not available in pipelines]
	  --overwrite					       Whether overwriting existing output dataset is allowed [not available in pipelines]
							       Mutually exclusive with --append
	  --append					       Append as a subdataset to existing output [not available in pipelines]
							       Mutually exclusive with --overwrite
	  --color-count <COLOR-COUNT>			       Select the number of colors in the generated color table (default: 256)
	  --color-map <COLOR-MAP>			       Color map filename
	  --output-nodata <OUTPUT-NODATA>		       Output nodata value
	  --no-dither					       Disable Floyd-Steinberg dithering
	  --bit-depth <BIT-DEPTH>			       Bit depth of color palette component (8 bit causes longer computation time). BIT-DEPTH=5|8 (default: 5)

	Advanced Options:
	  --if, --input-format <INPUT-FORMAT>		       Input formats [may be repeated] [not available in pipelines]
	  --oo, --open-option <KEY>=<VALUE>		       Open options [may be repeated] [not available in pipelines]

DESCRIPTION
     gdal raster rgb-to-palette computes an optimal  pseudo-color  table  for  a
     given  RGB  image	using  a  median cut algorithm on a downsampled RGB his-
     togram, unless a color table is provided with the --color-map option.  Then
     it converts the image into a pseudo-colored image using  the  color  table.
     This conversion utilizes by default Floyd-Steinberg dithering (error diffu-
     sion) to maximize output image visual quality.

     This  subcommand  is  also  available  as	a  potential step of gdal raster
     pipeline

GDALG OUTPUT (ON-THE-FLY / STREAMED DATASET)
     This program supports serializing the command line as a JSON file using the
     GDALG output format.  The resulting file can then be  opened  as  a  raster
     dataset  using  the  GDALG:  GDAL	Streamed Algorithm driver, and apply the
     specified pipeline in a on-the-fly / streamed way.

     NOTE:
	However this algorithm is  not	natively  streaming  compatible.  Conse-
	quently  a temporary dataset will be generated, which may cause signifi-
	cant processing time at opening.

PROGRAM-SPECIFIC OPTIONS
     --color-count <COLOR-COUNT>
	    Select the number of colors in the generated color	table.	Defaults
	    to 256.  Must be between 2 and 256.

     --color-map <FILENAME>
	    Extract  the  color  table	from <FILENAME> instead of computing it.
	    Can be used to have a consistent color  table  for	multiple  files.
	    The <FILENAME> must be either a raster file in a GDAL supported for-
	    mat with a palette or a color file in a supported format (.txt, QGIS
	    .qml, QGIS .qlr).

     --output-nodata <VALUE>
	    Added in version 3.13.

	    Specifies  the output nodata value, that will be used for input pix-
	    els at the source nodata value or that are transparent due to a mask
	    band, such as an alpha band. The destination nodata  value	must  be
	    between  0	and  255.   If	there  is  a  source  nodata  value or a
	    dataset-wide  mask	band  is  attached  to	the  source  bands,  and
	    --output-nodata is not specified, it defaults to 0.

     --no-dither
	    Added in version 3.13.

	    Disable  Floyd-Steinberg  dithering  (error  diffusion). This may be
	    useful to improve the compression rate by avoiding the "noise" added
	    by error diffusion.

     --bit-depth 5|8
	    Added in version 3.13.

	    Bit depth of each of the output color table R, G, B  component.  The
	    default  value  is 5, which means that each of the component is lim-
	    ited to 32 = 2 ^ 5 values. Setting bit depth to 8 increases the  fi-
	    delity  of	the output color table at the expense of longer computa-
	    tion time.

STANDARD OPTIONS
     --co, --creation-option <NAME>=<VALUE>
	    Many formats have one or more optional creation options that can  be
	    used  to  control  particulars about the file created. For instance,
	    the GeoTIFF driver supports creation options to control compression,
	    and whether the file should be tiled.

	    May be repeated.

	    The creation options available vary by format driver, and some  sim-
	    ple  formats have no creation options at all. A list of options sup-
	    ported for a format can be listed with the	--formats  command  line
	    option but the documentation for the format is the definitive source
	    of	information on driver creation options.  See Raster drivers for-
	    mat specific documentation for legal creation options for each  for-
	    mat.

     -f, --of, --format, --output-format <OUTPUT-FORMAT>
	    Which  output  raster  format to use. Allowed values may be given by
	    gdal --formats | grep raster | grep rw | sort

     --overwrite
	    Allow program to overwrite existing target file or dataset.   Other-
	    wise,  by default, gdal errors out if the target file or dataset al-
	    ready exists.

RETURN STATUS CODE
     The program returns status code 0 in case of success, and non-zero in  case
     of  error (non-blocking errors emitted as warnings are considered as a suc-
     cessful execution).

EXAMPLES
   Example 1
     Convert a TIFF file into a paletted PNG image

	$ gdal raster rgb-to-palette input.tif output.png

AUTHOR
     Even Rouault <even.rouault@spatialys.com>

COPYRIGHT
     1998-2026

				  Jun 05, 2026	   GDAL-RASTER-RGB-TO-PALETTE(1)

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