1GDAL_CALC(1) GDAL GDAL_CALC(1)
2
6 gdal_calc - Command line raster calculator with numpy syntax.
7
9 gdal_calc.py --calc=expression --outfile=out_filename [-A filename]
10 [--A_band=n] [-B...-Z filename] [other_options]
11 DESCRIPTION
13 Command line raster calculator with numpy syntax. Use any basic arith‐
15 metic supported by numpy arrays such as +, -, *, and / along with logi‐
16 cal operators such as >. Note that all files must have the same dimen‐
17 sions (unless extent option is used), but no projection checking is
18 performed (unless projectionCheck option is used).
19 --help Show this help message and exit
21 -h The same as --help.
23 --calc=expression
25 Calculation in numpy syntax using +, -, /, *, or any numpy array
26 functions (i.e. log10()). Multiple --calc options can be listed
27 to produce a multiband file (GDAL >= 3.2).
28 -A <filename>
30 Input gdal raster file, you can use any letter (a-z, A-Z).
31 (lower case supported since GDAL 3.3)
32 A letter may be repeated, or several values (separated by space)
34 can be provided (GDAL >= 3.3). Since GDAL 3.5, wildcard excep‐
35 tions (using ?, *) are supported for all shells/platforms. The
36 effect will be to create a 3-dim numpy array. In such a case,
37 the calculation formula must use this input as a 3-dim array and
38 must return a 2D array (see examples below). In case the calcu‐
39 lation does not return a 2D array an error would be generated.
40 --A_band=<n>
42 Number of raster band for file A (default 1).
43 --outfile=<filename>
45 Output file to generate or fill.
46 --NoDataValue=<value>
48 Output NoDataValue (default datatype specific value). To indi‐
49 cate not setting a NoDataValue use --NoDataValue=none (GDAL >=
50 3.3)
51 NOTE:
53 Using the Python API: None value will indicate default
54 datatype specific value. 'none' value will indicate not set‐
55 ting a NoDataValue.
56 --hideNoData
58 New in version 3.3.
59 Ignores the input bands NoDataValue. By default, the input
62 bands NoDataValue are not participating in the calculation. By
63 setting this setting - no special treatment will be performed on
64 the input NoDataValue. and they will be participating in the
65 calculation as any other value. The output will not have a set
66 NoDataValue, unless you explicitly specified a specific value by
67 setting --NoDataValue=<value>.
68 --type=<datatype>
70 Output datatype, must be one of [Byte, Int8, UInt16, Int16,
71 UInt32, Int32, UInt64, Int64, Float64, Float32, CInt16, CInt32,
72 CFloat64, CFloat32].
73 NOTE:
75 Despite the datatype set using --type, when doing intermedi‐
76 ate aritmethic operations using operands of the same type,
77 the operation result will honor the original datatype. This
78 may lead into unexpected results in the final result.
79 NOTE:
81 UInt64, Int64, CInt16, CInt32, CFloat32, CFloat64 have been
82 added in GDAL 3.5.3 Int8 has been added in GDAL 3.7
83 --format=<gdal_format>
85 GDAL format for output file.
86 --color-table=<filename>
88 Allows specifying a filename of a color table (or a ColorTable
89 object) (with Palette Index interpretation) to be used for the
90 output raster. Supported formats: txt (i.e. like gdaldem, but
91 color names are not supported), qlr, qml (i.e. exported from
92 QGIS)
93 --extent=<option>
95 New in version 3.3.
96 This option determines how to handle rasters with different ex‐
99 tents. This option is mutually exclusive with the projwin op‐
100 tion, which is used for providing a custom extent.
101 For all the options below the pixel size (resolution) and SRS
103 (Spatial Reference System) of all the input rasters must be the
104 same.
105 ignore (default) - only the dimensions of the rasters are com‐
107 pared. if the dimensions do not agree the operation will fail.
108 fail - the dimensions and the extent (bounds) of the rasters
110 must agree, otherwise the operation will fail.
111 union - the extent (bounds) of the output will be the minimal
113 rectangle that contains all the input extents.
114 intersect - the extent (bounds) of the output will be the maxi‐
116 mal rectangle that is contained in all the input extents.
117 --projwin <ulx> <uly> <lrx> <lry>
119 New in version 3.3.
120 This option provides a custom extent for the output, it is mutu‐
123 ally exclusive with the extent option.
124 --projectionCheck
126 New in version 3.3.
127 By default, no projection checking will be performed. By set‐
130 ting this option, if the projection is not the same for all
131 bands then the operation will fail.
132 --creation-option=<option>
134 Passes a creation option to the output format driver. Multiple
135 options may be listed. See format specific documentation for le‐
136 gal creation options for each format.
137 --co=<option>
139 The same as creation-option.
140 --allBands=[a-z, A-Z]
142 Process all bands of given raster (a-z, A-Z). Requires a single
143 calc for all bands.
144 --overwrite
146 Overwrite output file if it already exists. Overwriting must be
147 understood here as deleting and recreating the file from
148 scratch. Note that if this option is not specified and the out‐
149 put file already exists, it will be updated in place.
150 --debug
152 Print debugging information.
153 --quiet
155 Suppress progress messages.
156
158 New in version 3.3.
159 The following options are available by using function the python inter‐
162 face of gdal_calc. They are not available using the command prompt.
163 user_namespace
165 A dictionary of custom functions or other names to be available
166 for use in the Calc expression.
167 return_ds
169 If enabled, the output dataset would be returned from the func‐
170 tion and not closed.
171 color_table
173 Allows specifying a ColorTable object (with Palette Index inter‐
174 pretation) to be used for the output raster.
175
177 Add two files together:
178 gdal_calc.py -A input1.tif -B input2.tif --outfile=result.tif --calc="A+B"
180 Average of two layers:
182 gdal_calc.py -A input1.tif -B input2.tif --outfile=result.tif --calc="(A+B)/2"
184 NOTE:
186 In the previous example, beware that if A and B inputs are of the
187 same datatype, for example integers, you may need to force the con‐
188 version of one of the operands before the division operation.
189 gdal_calc.py -A input.tif -B input2.tif --outfile=result.tif --calc="(A.astype(numpy.float64) + B) / 2"
191 Add three files together (two options with the same result):
193 gdal_calc.py -A input1.tif -B input2.tif -C input3.tif --outfile=result.tif --calc="A+B+C"
195 New in version 3.3.
197 gdal_calc.py -A input1.tif -A input2.tif -A input3.tif --outfile=result.tif --calc="numpy.sum(A,axis=0)".
200 Average of three layers (two options with the same result):
202 gdal_calc.py -A input1.tif -B input2.tif -C input3.tif --outfile=result.tif --calc="(A+B+C)/3"
204 New in version 3.3.
206 gdal_calc.py -A input1.tif input2.tif input3.tif --outfile=result.tif --calc="numpy.average(a,axis=0)".
209 Maximum of three layers (two options with the same result):
211 gdal_calc.py -A input1.tif -B input2.tif -C input3.tif --outfile=result.tif --calc="numpy.max((A,B,C),axis=0)"
213 New in version 3.3.
215 gdal_calc.py -A input1.tif input2.tif input3.tif --outfile=result.tif --calc="numpy.max(A,axis=0)"
218 Set values of zero and below to null:
220 gdal_calc.py -A input.tif --outfile=result.tif --calc="A*(A>0)" --NoDataValue=0
222 Using logical operator to keep a range of values from input:
224 gdal_calc.py -A input.tif --outfile=result.tif --calc="A*logical_and(A>100,A<150)"
226 Work with multiple bands:
228 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)"
230
232 Chris Yesson <chris dot yesson at ioz dot ac dot uk>, Etienne Tourigny
233 <etourigny dot dev at gmail dot com>
234
236 1998-2023
237 Oct 30, 2023 GDAL_CALC(1)