1GDALBUILDVRT(1) GDAL GDALBUILDVRT(1)
2
6 gdalbuildvrt - Builds a VRT from a list of datasets.
7
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 [-optim {[AUTO]/VECTOR/RASTER}]
15 [-addalpha] [-hidenodata]
16 [-srcnodata "value [value...]"] [-vrtnodata "value [value...]"]
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]*
21
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
32 mosaic 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 prioritary datasets, but currently, alpha channel is not taken
49 into account to do alpha compositing (so a source with alpha=0 appear‐
50 ing on top of another source will override is content). This might be
51 changed in later versions.
52 -tileindex
54 Use the specified value as the tile index field, instead of the
55 default value with 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
69 dimensions 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
86 expressed in georeferenced units. If not specified, the extent
87 of 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
112 intrinsic nodata settings on the source datasets will be used
113 (if they exist). The value set by this option is written in the
114 NODATA element of each ComplexSource element. Use a value of
115 None to ignore intrinsic nodata settings on the source datasets.
116 -b <band>
118 Select an input <band> to be processed. Bands are numbered from
119 1. If input bands not set all bands will be added to vrt. Mul‐
120 tiple -b switches may be used to select a set of input bands.
121 -sd< <subdataset>
123 If the input dataset contains several subdatasets use a sub‐
124 dataset with the specified number (starting from 1). This is an
125 alternative of giving the full subdataset name as an input.
126 -vrtnodata <value> [<value>...]
128 Set nodata values at the VRT band level (different values can be
129 supplied for each band). If more than one value is supplied all
130 values should be quoted to keep them together as a single oper‐
131 ating system argument. If the option is not specified, intrin‐
132 sic nodata settings on the first dataset will be used (if they
133 exist). The value set by this option is written in the
134 NoDataValue element of each VRTRasterBand element. Use a value
135 of None to ignore intrinsic nodata settings on the source
136 datasets.
137 -separate
139 Place each input file into a separate band. In that case, only
140 the first band of each dataset will be placed into a new band.
141 Contrary to the default mode, it is not required that all bands
142 have the same datatype.
143 -allow_projection_difference
145 When this option is specified, the utility will accept to make a
146 VRT even if the input datasets have not the same projection.
147 Note: this does not mean that they will be reprojected. Their
148 projection will just be ignored.
149 -optim {[AUTO]/VECTOR/RASTER}}
151 Force the algorithm used (results are identical). The raster
152 mode is used in most cases and optimise read/write operations.
153 The vector mode is useful with a decent amount of input features
154 and optimise the CPU use. That mode have to be used with tiled
155 images to be efficient. The auto mode (the default) will chose
156 the algorithm based on input and output properties.
157 New in version 2.3.
159 -a_srs <srs_def>
162 Override the projection for the output file. The <srs_def> may
163 be any of the usual GDAL/OGR forms, complete WKT, PROJ.4, EPSG:n
164 or a file containing the WKT. No reprojection is done.
165 -r {nearest (default),bilinear,cubic,cubicspline,lanczos,average,mode}
167 Select a resampling algorithm.
168 -oo NAME=VALUE
170 Dataset open option (format specific)
171 New in version 2.2.
173 -input_file_list <mylist.txt>
176 To specify a text file with an input filename on each line
177 -q To disable the progress bar on the console
179 -overwrite
181 Overwrite the VRT if it already exists.
182
184 · Make a virtual mosaic from all TIFF files contained in a directory :
185 gdalbuildvrt doq_index.vrt doq/*.tif
187 · Make a virtual mosaic from files whose name is specified in a text
189 file :
190 gdalbuildvrt -input_file_list my_list.txt doq_index.vrt
192 · Make a RGB virtual mosaic from 3 single-band input files :
194 gdalbuildvrt -separate rgb.vrt red.tif green.tif blue.tif
196 · Make a virtual mosaic with blue background colour (RGB: 0 0 255) :
198 gdalbuildvrt -hidenodata -vrtnodata "0 0 255" doq_index.vrt doq/*.tif
200
202 Even Rouault <even.rouault@spatialys.com>
203
205 1998-2021
206 Jan 05, 2021 GDALBUILDVRT(1)