1GDALBUILDVRT(1) GDAL GDALBUILDVRT(1)
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6 gdalbuildvrt - Builds a VRT from a list of datasets.
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9 gdalbuildvrt [-tileindex field_name]
10 [-resolution {highest|lowest|average|user}]
11 [-te xmin ymin xmax ymax] [-tr xres yres] [-tap]
12 [-separate] [-b band]* [-sd subdataset]
13 [-allow_projection_difference] [-q]
14 [-addalpha] [-hidenodata]
15 [-srcnodata "value [value...]"] [-vrtnodata "value [value...]"]
16 [-ignore_srcmaskband]
17 [-a_srs srs_def]
18 [-r {nearest,bilinear,cubic,cubicspline,lanczos,average,mode}]
19 [-oo NAME=VALUE]*
20 [-input_file_list my_list.txt] [-overwrite] output.vrt [gdalfile]*
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23 This program builds a VRT (Virtual Dataset) that is a mosaic of the
24 list of input GDAL datasets. The list of input GDAL datasets can be
25 specified at the end of the command line, or put in a text file (one
26 filename per line) for very long lists, or it can be a MapServer
27 tileindex (see ref gdaltindex utility). In the later case, all entries
28 in the tile index will be added to the VRT.
29 With -separate, each files goes into a separate band in the VRT
31 dataset. Otherwise, the files are considered as tiles of a larger mo‐
32 saic and the VRT file has as many bands as one of the input files.
33 If one GDAL dataset is made of several subdatasets and has 0 raster
35 bands, all the subdatasets will be added to the VRT rather than the
36 dataset itself.
37 gdalbuildvrt does some amount of checks to assure that all files that
39 will be put in the resulting VRT have similar characteristics : number
40 of bands, projection, color interpretation... If not, files that do not
41 match the common characteristics will be skipped. (This is only true
42 in the default mode, and not when using the -separate option)
43 If there is some amount of spatial overlapping between files, the order
45 of files appearing in the list of source matter: files that are listed
46 at the end are the ones from which the content will be fetched. Note
47 that nodata will be taken into account to potentially fetch data from
48 less priority datasets, but currently, alpha channel is not taken into
49 account to do alpha compositing (so a source with alpha=0 appearing on
50 top of another source will override is content). This might be changed
51 in later versions.
52 -tileindex
54 Use the specified value as the tile index field, instead of the
55 default value which is 'location'.
56 -resolution {highest|lowest|average|user}
58 In case the resolution of all input files is not the same, the
59 -resolution flag enables the user to control the way the output
60 resolution is computed.
61 highest will pick the smallest values of pixel dimensions within
63 the set of source rasters.
64 lowest will pick the largest values of pixel dimensions within
66 the set of source rasters.
67 average is the default and will compute an average of pixel di‐
69 mensions within the set of source rasters.
70 user must be used in combination with the -tr option to specify
72 the target resolution.
73 -tr <res> <yres>
75 Set target resolution. The values must be expressed in georefer‐
76 enced units. Both must be positive values. Specifying those
77 values is of course incompatible with highest|lowest|average
78 values for -resolution option.
79 -tap (target aligned pixels) align the coordinates of the extent of
81 the output file to the values of the -tr, such that the aligned
82 extent includes the minimum extent.
83 -te xmin ymin xmax ymax
85 Set georeferenced extents of VRT file. The values must be ex‐
86 pressed in georeferenced units. If not specified, the extent of
87 the VRT is the minimum bounding box of the set of source
88 rasters.
89 -addalpha
91 Adds an alpha mask band to the VRT when the source raster have
92 none. Mainly useful for RGB sources (or grey-level sources).
93 The alpha band is filled on-the-fly with the value 0 in areas
94 without any source raster, and with value 255 in areas with
95 source raster. The effect is that a RGBA viewer will render the
96 areas without source rasters as transparent and areas with
97 source rasters as opaque. This option is not compatible with
98 -separate.
99 -hidenodata
101 Even if any band contains nodata value, giving this option makes
102 the VRT band not report the NoData. Useful when you want to con‐
103 trol the background color of the dataset. By using along with
104 the -addalpha option, you can prepare a dataset which doesn't
105 report nodata value but is transparent in areas with no data.
106 -srcnodata <value> [<value>...]
108 Set nodata values for input bands (different values can be sup‐
109 plied for each band). If more than one value is supplied all
110 values should be quoted to keep them together as a single oper‐
111 ating system argument. If the option is not specified, the in‐
112 trinsic nodata settings on the source datasets will be used (if
113 they exist). The value set by this option is written in the NO‐
114 DATA element of each ComplexSource element. Use a value of None
115 to ignore intrinsic nodata settings on the source datasets.
116 -ignore_srcmaskband
118 New in version 3.3.
119 Starting with GDAL 3.3, if a source has a mask band (inter‐
122 nal/external mask band, or alpha band), a <ComplexSource> ele‐
123 ment is created by default with a <UseMaskBand>true</Use‐
124 MaskBand> child element, to instruct the VRT driver to use the
125 mask band of the source to mask pixels being composited. This is
126 a generalization of the NODATA element. When specifying the
127 -ignore_srcmaskband option, the mask band of sources will not be
128 taken into account, and in case of overlapping between sources,
129 the last one will override previous ones in areas of overlap.
130 -b <band>
132 Select an input <band> to be processed. Bands are numbered from
133 1. If input bands not set all bands will be added to vrt. Mul‐
134 tiple -b switches may be used to select a set of input bands.
135 -sd< <subdataset>
137 If the input dataset contains several subdatasets use a sub‐
138 dataset with the specified number (starting from 1). This is an
139 alternative of giving the full subdataset name as an input.
140 -vrtnodata <value> [<value>...]
142 Set nodata values at the VRT band level (different values can be
143 supplied for each band). If more than one value is supplied all
144 values should be quoted to keep them together as a single oper‐
145 ating system argument. If the option is not specified, intrin‐
146 sic nodata settings on the first dataset will be used (if they
147 exist). The value set by this option is written in the No‐
148 DataValue element of each VRTRasterBand element. Use a value of
149 None to ignore intrinsic nodata settings on the source datasets.
150 -separate
152 Place each input file into a separate band. In that case, only
153 the first band of each dataset will be placed into a new band.
154 Contrary to the default mode, it is not required that all bands
155 have the same datatype.
156 -allow_projection_difference
158 When this option is specified, the utility will accept to make a
159 VRT even if the input datasets have not the same projection.
160 Note: this does not mean that they will be reprojected. Their
161 projection will just be ignored.
162 -a_srs <srs_def>
164 Override the projection for the output file. The <srs_def> may
165 be any of the usual GDAL/OGR forms, complete WKT, PROJ.4, EPSG:n
166 or a file containing the WKT. No reprojection is done.
167 -r {nearest (default),bilinear,cubic,cubicspline,lanczos,average,mode}
169 Select a resampling algorithm.
170 -oo NAME=VALUE
172 Dataset open option (format specific)
173 New in version 2.2.
175 -input_file_list <mylist.txt>
178 To specify a text file with an input filename on each line
179 -q To disable the progress bar on the console
181 -overwrite
183 Overwrite the VRT if it already exists.
184
186 • Make a virtual mosaic from all TIFF files contained in a directory :
187 gdalbuildvrt doq_index.vrt doq/*.tif
189 • Make a virtual mosaic from files whose name is specified in a text
191 file :
192 gdalbuildvrt -input_file_list my_list.txt doq_index.vrt
194 • Make a RGB virtual mosaic from 3 single-band input files :
196 gdalbuildvrt -separate rgb.vrt red.tif green.tif blue.tif
198 • Make a virtual mosaic with blue background colour (RGB: 0 0 255) :
200 gdalbuildvrt -hidenodata -vrtnodata "0 0 255" doq_index.vrt doq/*.tif
202
204 Even Rouault <even.rouault@spatialys.com>
205
207 1998-2021
208 Sep 07, 2021 GDALBUILDVRT(1)