GDAL_CALC(1)                         GDAL                         GDAL_CALC(1)

NAME
       gdal_calc - Command line raster calculator with numpy syntax.

SYNOPSIS

          gdal_calc.py [--help] [--help-general]
                       --calc=expression --outfile=<out_filename> [-A <filename>]
                       [--A_band=<n>] [-B...-Z <filename>] [<other_options>]

       DESCRIPTION

       Command line raster calculator with numpy syntax. Use any basic
       arithmetic supported by numpy arrays such as +, -, *, and / along with
       logical operators such as >.  Note that all files must have the same
       dimensions (unless extent option is used), but no projection checking
       is performed (unless projectionCheck option is used).

       --help Show this help message and exit

       --help-general
              Gives a brief usage message for the generic GDAL commandline
              options and exit.

       --calc=<expression>
              Calculation in numpy syntax using +, -, /, *, or any numpy array
              functions (i.e. log10()).  Multiple --calc options can be listed
              to produce a multiband file (GDAL >= 3.2).

       -A <filename>
              Input gdal raster file, you can use any letter (a-z, A-Z).
              (lower case supported since GDAL 3.3)

              A letter may be repeated, or several values (separated by space)
              can be provided (GDAL >= 3.3).  Since GDAL 3.5, wildcard
              exceptions (using ?, *) are supported for all shells/platforms.
              The effect will be to create a 3-dim numpy array.  In such a
              case, the calculation formula must use this input as a 3-dim
              array and must return a 2D array (see examples below).  In case
              the calculation does not return a 2D array an error would be
              generated.

       --A_band=<n>
              Number of raster band for file A (default 1).

       --outfile=<filename>
              Output file to generate or fill.

       --NoDataValue=<value>
              Output NoDataValue (default datatype specific value).  To
              indicate not setting a NoDataValue use --NoDataValue=none (GDAL
              >= 3.3)

              NOTE:
                 Using the Python API: None value will indicate default
                 datatype specific value.  'none' value will indicate not
                 setting a NoDataValue.

       --hideNoData
              New in version 3.3.


              Ignores the input bands NoDataValue.  By default, the input
              bands NoDataValue are not participating in the calculation.  By
              setting this setting - no special treatment will be performed on
              the input NoDataValue. and they will be participating in the
              calculation as any other value.  The output will not have a set
              NoDataValue, unless you explicitly specified a specific value by
              setting --NoDataValue=<value>.

       --type=<datatype>
              Output datatype, must be one of [Byte, Int8, UInt16, Int16,
              UInt32, Int32, UInt64, Int64, Float64, Float32, CInt16, CInt32,
              CFloat64, CFloat32].

              NOTE:
                 Despite the datatype set using --type, when doing
                 intermediate aritmethic operations using operands of the same
                 type, the operation result will honor the original datatype.
                 This may lead into unexpected results in the final result.

              NOTE:
                 UInt64, Int64, CInt16, CInt32, CFloat32, CFloat64 have been
                 added in GDAL 3.5.3 Int8 has been added in GDAL 3.7

       --format=<gdal_format>
              GDAL format for output file.

       --color-table=<filename>
              Allows specifying a filename of a color table (or a ColorTable
              object) (with Palette Index interpretation) to be used for the
              output raster.  Supported formats: txt (i.e. like gdaldem, but
              color names are not supported), qlr, qml (i.e. exported from
              QGIS)

       --extent=<option>
              New in version 3.3.


              This option determines how to handle rasters with different
              extents.  This option is mutually exclusive with the projwin
              option, which is used for providing a custom extent.

              For all the options below the pixel size (resolution) and SRS
              (Spatial Reference System) of all the input rasters must be the
              same.

              ignore (default) - only the dimensions of the rasters are
              compared. if the dimensions do not agree the operation will
              fail.

              fail - the dimensions and the extent (bounds) of the rasters
              must agree, otherwise the operation will fail.

              union - the extent (bounds) of the output will be the minimal
              rectangle that contains all the input extents.

              intersect - the extent (bounds) of the output will be the
              maximal rectangle that is contained in all the input extents.

       --projwin <ulx> <uly> <lrx> <lry>
              New in version 3.3.


              This option provides a custom extent for the output, it is
              mutually exclusive with the extent option.

       --projectionCheck
              New in version 3.3.


              By default, no projection checking will be performed.  By
              setting this option, if the projection is not the same for all
              bands then the operation will fail.

       --creation-option=<option>
              Passes a creation option to the output format driver.  Multiple
              options may be listed. See format specific documentation for
              legal creation options for each format.

       --co=<option>
              The same as creation-option.

       --allBands=[a-z, A-Z]
              Process all bands of given raster (a-z, A-Z). Requires a single
              calc for all bands.

       --overwrite
              Overwrite output file if it already exists. Overwriting must be
              understood here as deleting and recreating the file from
              scratch. Note that if this option is not specified and the
              output file already exists, it will be updated in place.

       --debug
              Print debugging information.

       --quiet
              Suppress progress messages.

PYTHON OPTIONS
       New in version 3.3.


       The following options are available by using function the python
       interface of gdal_calc.  They are not available using the command
       prompt.

       user_namespace
              A dictionary of custom functions or other names to be available
              for use in the Calc expression.

       return_ds
              If enabled, the output dataset would be returned from the
              function and not closed.

       color_table
              Allows specifying a ColorTable object (with Palette Index
              interpretation) to be used for the output raster.

EXAMPLE
       Add two files together:

          gdal_calc.py -A input1.tif -B input2.tif --outfile=result.tif --calc="A+B"

       Average of two layers:

          gdal_calc.py -A input1.tif -B input2.tif --outfile=result.tif --calc="(A+B)/2"

       NOTE:
          In the previous example, beware that if A and B inputs are of the
          same datatype, for example integers, you may need to force the
          conversion of one of the operands before the division operation.

             gdal_calc.py -A input.tif -B input2.tif --outfile=result.tif --calc="(A.astype(numpy.float64) + B) / 2"

       Add three files together (two options with the same result):

          gdal_calc.py -A input1.tif -B input2.tif -C input3.tif --outfile=result.tif --calc="A+B+C"

       New in version 3.3.


          gdal_calc.py -A input1.tif -A input2.tif -A input3.tif --outfile=result.tif --calc="numpy.sum(A,axis=0)".

       Average of three layers (two options with the same result):

          gdal_calc.py -A input1.tif -B input2.tif -C input3.tif --outfile=result.tif --calc="(A+B+C)/3"

       New in version 3.3.


          gdal_calc.py -A input1.tif input2.tif input3.tif --outfile=result.tif --calc="numpy.average(a,axis=0)".

       Maximum of three layers  (two options with the same result):

          gdal_calc.py -A input1.tif -B input2.tif -C input3.tif --outfile=result.tif --calc="numpy.max((A,B,C),axis=0)"

       New in version 3.3.


          gdal_calc.py -A input1.tif input2.tif input3.tif --outfile=result.tif --calc="numpy.max(A,axis=0)"

       Set values of zero and below to null:

          gdal_calc.py -A input.tif --outfile=result.tif --calc="A*(A>0)" --NoDataValue=0

       Using logical operator to keep a range of values from input:

          gdal_calc.py -A input.tif --outfile=result.tif --calc="A*logical_and(A>100,A<150)"

       Work with multiple bands:

          gdal_calc.py -A input.tif --A_band=1 -B input.tif --B_band=2 --outfile=result.tif --calc="(A+B)/2" --calc="B*logical_and(A>100,A<150)"

AUTHOR
       Chris Yesson <chris dot yesson at ioz dot ac dot uk>, Etienne Tourigny
       <etourigny dot dev at gmail dot com>

COPYRIGHT
       1998-2024

                                 April 2, 2024                    GDAL_CALC(1)