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GDAL_CALC(1) GDAL GDAL_CALC(1) NAME gdal_calc - Command line raster calculator with numpy syntax. SYNOPSIS gdal_calc [--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 arith- metic supported by numpy arrays such as +, -, *, and / along with logi- cal operators such as >. Note that all files must have the same dimen- sions (unless extent option is used), but no projection checking is performed (unless projectionCheck option is used). NOTE: gdal_calc is a Python utility, and is only available if GDAL Python bindings are available. --help Show this help message and exit --help-general Gives a brief usage message for the generic GDAL commandline op- tions 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 excep- tions (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 calcu- lation 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 indi- cate 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 set- ting 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 intermedi- ate arithmetic 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 ex- tents. This option is mutually exclusive with the projwin op- tion, 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 com- pared. 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 maxi- mal 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 mutu- ally exclusive with the extent option. --projectionCheck New in version 3.3. By default, no projection checking will be performed. By set- ting 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 le- gal 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 out- put 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 inter- face 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 func- tion and not closed. color_table Allows specifying a ColorTable object (with Palette Index inter- pretation) to be used for the output raster. EXAMPLES Add two files together: gdal_calc -A input1.tif -B input2.tif --outfile=result.tif --calc="A+B" Average of two layers: gdal_calc -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 con- version of one of the operands before the division operation. gdal_calc -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 -A input1.tif -B input2.tif -C input3.tif --outfile=result.tif --calc="A+B+C" gdal_calc -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 -A input1.tif -B input2.tif -C input3.tif --outfile=result.tif --calc="(A+B+C)/3" gdal_calc -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 -A input1.tif -B input2.tif -C input3.tif --outfile=result.tif --calc="numpy.max((A,B,C),axis=0)" gdal_calc -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 -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 -A input.tif --outfile=result.tif --calc="A*logical_and(A>100,A<150)" Work with multiple bands: gdal_calc -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 1998-2025 Feb 11, 2025 GDAL_CALC(1)
NAME | SYNOPSIS | PYTHON OPTIONS | EXAMPLES | AUTHOR | COPYRIGHT
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