1GDAL_CALC(1) GDAL GDAL_CALC(1)
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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 [Int32, Int16, Float64, UInt16,
71 Byte, UInt32, Float32].
72 NOTE:
74 Despite the datatype set using --type, when doing intermedi‐
75 ate aritmethic operations using operands of the same type,
76 the operation result will honor the original datatype. This
77 may lead into unexpected results in the final result.
78 --format=<gdal_format>
80 GDAL format for output file.
81 --color-table=<filename>
83 Allows specifying a filename of a color table (or a ColorTable
84 object) (with Palette Index interpretation) to be used for the
85 output raster. Supported formats: txt (i.e. like gdaldem, but
86 color names are not supported), qlr, qml (i.e. exported from
87 QGIS)
88 --extent=<option>
90 New in version 3.3.
91 This option determines how to handle rasters with different ex‐
94 tents. This option is mutually exclusive with the projwin op‐
95 tion, which is used for providing a custom extent.
96 For all the options below the pixel size (resolution) and SRS
98 (Spatial Reference System) of all the input rasters must be the
99 same.
100 ignore (default) - only the dimensions of the rasters are com‐
102 pared. if the dimensions do not agree the operation will fail.
103 fail - the dimensions and the extent (bounds) of the rasters
105 must agree, otherwise the operation will fail.
106 union - the extent (bounds) of the output will be the minimal
108 rectangle that contains all the input extents.
109 intersect - the extent (bounds) of the output will be the maxi‐
111 mal rectangle that is contained in all the input extents.
112 --projwin <ulx> <uly> <lrx> <lry>
114 New in version 3.3.
115 This option provides a custom extent for the output, it is mutu‐
118 ally exclusive with the extent option.
119 --projectionCheck
121 New in version 3.3.
122 By default, no projection checking will be performed. By set‐
125 ting this option, if the projection is not the same for all
126 bands then the operation will fail.
127 --creation-option=<option>
129 Passes a creation option to the output format driver. Multiple
130 options may be listed. See format specific documentation for le‐
131 gal creation options for each format.
132 --co=<option>
134 The same as creation-option.
135 --allBands=[a-z, A-Z]
137 Process all bands of given raster (a-z, A-Z). Requires a single
138 calc for all bands.
139 --overwrite
141 Overwrite output file if it already exists. Overwriting must be
142 understood here as deleting and recreating the file from
143 scratch. Note that if this option is not specified and the out‐
144 put file already exists, it will be updated in place.
145 --debug
147 Print debugging information.
148 --quiet
150 Suppress progress messages.
151
153 New in version 3.3.
154 The following options are available by using function the python inter‐
157 face of gdal_calc. They are not available using the command prompt.
158 user_namespace
160 A dictionary of custom functions or other names to be available
161 for use in the Calc expression.
162 return_ds
164 If enabled, the output dataset would be returned from the func‐
165 tion and not closed.
166 color_table
168 Allows specifying a ColorTable object (with Palette Index inter‐
169 pretation) to be used for the output raster.
170
172 Add two files together:
173 gdal_calc.py -A input1.tif -B input2.tif --outfile=result.tif --calc="A+B"
175 Average of two layers:
177 gdal_calc.py -A input1.tif -B input2.tif --outfile=result.tif --calc="(A+B)/2"
179 NOTE:
181 In the previous example, beware that if A and B inputs are of the
182 same datatype, for example integers, you may need to force the con‐
183 version of one of the operands before the division operation.
184 gdal_calc.py -A input.tif -B input2.tif --outfile=result.tif --calc="(A.astype(numpy.float64) + B) / 2"
186 Add three files together (two options with the same result):
188 gdal_calc.py -A input1.tif -B input2.tif -C input3.tif --outfile=result.tif --calc="A+B+C"
190 New in version 3.3.
192 gdal_calc.py -A input1.tif -A input2.tif -A input3.tif --outfile=result.tif --calc="numpy.sum(A,axis=0)".
195 Average of three layers (two options with the same result):
197 gdal_calc.py -A input1.tif -B input2.tif -C input3.tif --outfile=result.tif --calc="(A+B+C)/3"
199 New in version 3.3.
201 gdal_calc.py -A input1.tif input2.tif input3.tif --outfile=result.tif --calc="numpy.average(a,axis=0)".
204 Maximum of three layers (two options with the same result):
206 gdal_calc.py -A input1.tif -B input2.tif -C input3.tif --outfile=result.tif --calc="numpy.max((A,B,C),axis=0)"
208 New in version 3.3.
210 gdal_calc.py -A input1.tif input2.tif input3.tif --outfile=result.tif --calc="numpy.max(A,axis=0)"
213 Set values of zero and below to null:
215 gdal_calc.py -A input.tif --outfile=result.tif --calc="A*(A>0)" --NoDataValue=0
217 Using logical operator to keep a range of values from input:
219 gdal_calc.py -A input.tif --outfile=result.tif --calc="A*logical_and(A>100,A<150)"
221 Work with multiple bands:
223 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)"
225
227 Chris Yesson <chris dot yesson at ioz dot ac dot uk>, Etienne Tourigny
228 <etourigny dot dev at gmail dot com>
229
231 1998-2022
232 Sep 02, 2022 GDAL_CALC(1)