GDAL-RASTER-NODATA-TO-ALPHA(1) GDAL GDAL-RASTER-NODATA-TO-ALPHA(1)
NAME
gdal-raster-nodata-to-alpha - Replace nodata value(s) with an alpha
band
Added in version 3.12.
SYNOPSIS
Usage: gdal raster nodata-to-alpha [OPTIONS]
Replace nodata value(s) with an alpha band.
Positional arguments:
-i, --input Input raster datasets [required] [not available in pipelines]
-o, --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 = 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 ("GDALG" allowed) [not available in pipelines]
--co, --creation-option = 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
--nodata Override nodata value of input band(s) (numeric value, 'nan', 'inf', '-inf') [may be repeated]
Advanced Options:
--if, --input-format Input formats [may be repeated] [not available in pipelines]
--oo, --open-option = Open options [may be repeated] [not available in pipelines]
DESCRIPTION
gdal raster nodata-to-alpha adds an alpha band based on the nodata
value metadata set on the bands of the input dataset.
If there is no explicit nodata value on the input dataset, it is
possible to add it with the --nodata option.
This program is a no-op and can be safely used if the input dataset has
no nodata value and --nodata is not specified.
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.
PROGRAM-SPECIFIC OPTIONS
--nodata
Override nodata value of input band(s) (numeric value, 'nan',
'inf', '-inf'). Either one value can be specified or as many
values as they are input bands. When multiple values are
specified, a pixel is considered as invalid only if it matches
the nodata values on all bands.
STANDARD OPTIONS
--co, --creation-option =
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
simple formats have no creation options at all. A list of
options supported 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 format specific documentation for legal
creation options for each format.
-f, --of, --format, --output-format
Which output raster format to use. Allowed values may be given
by gdal --formats | grep raster | grep rw | sort
--ot, --datatype, --output-data-type
Output data type among Byte, Int8, UInt16, Int16, UInt32, Int32,
UInt64, Int64, CInt16, CInt32, Float32, Float64, CFloat32,
CFloat64.
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 successful execution).
EXAMPLES
Example 1
$ gdal raster nodata-to-alpha input_with_nodata.tif output_with_alpha_band.tif
AUTHOR
Even Rouault
COPYRIGHT
1998-2026
August 18, 2026 GDAL-RASTER-NODATA-TO-ALPHA(1)