1gdalbuildvrt(1) General Commands Manual gdalbuildvrt(1)
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6 gdalbuildvrt - .TH "gdalbuildvrt" 1 "Fri Apr 22 2011" "GDAL"
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9 gdalbuildvrt - Builds a VRT from a list of datasets. (compiled by
10 default since GDAL 1.6.1)
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13 gdalbuildvrt [-tileindex field_name] [-resolution {highest|lowest|average|user}]
14 [-tr xres yres] [-separate] [-allow_projection_difference] [-q]
15 [-te xmin ymin xmax ymax] [-addalpha] [-hidenodata]
16 [-srcnodata "value [value...]"] [-vrtnodata "value [value...]"]
17 [-input_file_list my_liste.txt] output.vrt [gdalfile]*
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20 This program builds a VRT (Virtual Dataset) that is a mosaic of the
21 list of input gdal datasets. The list of input gdal datasets can be
22 specified at the end of the command line, or put in a text file (one
23 filename per line) for very long lists, or it can be a MapServer
24 tileindex (see gdaltindex utility). In the later case, all entries in
25 the tile index will be added to the VRT.
26 With -separate, each files goes into a separate stacked band in the VRT
28 band. Otherwise, the files are considered as tiles of a larger mosaic
29 and the VRT file has as many bands as one of the input files.
30 If one GDAL dataset is made of several subdatasets and has 0 raster
32 bands, all the subdatasets will be added to the VRT rather than the
33 dataset itself.
34 gdalbuildvrt does some amount of checks to assure that all files that
36 will be put in the resulting VRT have similar characteristics : number
37 of bands, projection, color interpretation... If not, files that do not
38 match the common characteristics will be skipped. (This is only true in
39 the default mode, and not when using the -separate option)
40 If there is some amount of spatial overlapping between files, the order
42 may depend on the order they are inserted in the VRT file, but this
43 behaviour should not be relied on.
44 This utility is somehow equivalent to the gdal_vrtmerge.py utility and
46 is build by default in GDAL 1.6.1.
47 -tileindex:
49 Use the specified value as the tile index field, instead of the
50 default value with is 'location'.
51 -resolution {highest|lowest|average|user}:
53 In case the resolution of all input files is not the same, the
54 -resolution flag enables the user to control the way the output
55 resolution is computed. 'average' is the default. 'highest' will
56 pick the smallest values of pixel dimensions within the set of
57 source rasters. 'lowest' will pick the largest values of pixel
58 dimensions within the set of source rasters. 'average' will compute
59 an average of pixel dimensions within the set of source rasters.
60 'user' is new in GDAL 1.7.0 and must be used in combination with
61 the -tr option to specify the target resolution.
62 -tr xres yres :
64 (starting with GDAL 1.7.0) set target resolution. The values must
65 be expressed in georeferenced units. Both must be positive values.
66 Specifying those values is of curse incompatible with
67 highest|lowest|average values for -resolution option.
68 -te xmin ymin xmax ymax :
70 (starting with GDAL 1.7.0) set georeferenced extents of VRT file.
71 The values must be expressed in georeferenced units. If not
72 specified, the extent of the VRT is the minimum bounding box of the
73 set of source rasters.
74 -addalpha:
76 (starting with GDAL 1.7.0) Adds an alpha mask band to the VRT when
77 the source raster have none. Mainly useful for RGB sources (or
78 grey-level sources). The alpha band is filled on-the-fly with the
79 value 0 in areas without any source raster, and with value 255 in
80 areas with source raster. The effect is that a RGBA viewer will
81 render the areas without source rasters as transparent and areas
82 with source rasters as opaque. This option is not compatible with
83 -separate.
84 -hidenodata:
86 (starting with GDAL 1.7.0) Even if any band contains nodata value,
87 giving this option makes the VRT band not report the NoData. Useful
88 when you want to control the background color of the dataset. By
89 using along with the -addalpha option, you can prepare a dataset
90 which doesn't report nodata value but is transparent in areas with
91 no data.
92 -srcnodata value [value...]:
94 (starting with GDAL 1.7.0) Set nodata values for input bands
95 (different values can be supplied for each band). If more than one
96 value is supplied all values should be quoted to keep them together
97 as a single operating system argument. If the option is not
98 specified, the instrinsic nodata settings on the source datasets
99 will be used (if they exist). The value set by this option is
100 written in the NODATA element of each ComplexSource element. Use a
101 value of None to ignore intrinsic nodata settings on the source
102 datasets.
103 -vrtnodata value [value...]:
105 (starting with GDAL 1.7.0) Set nodata values at the VRT band level
106 (different values can be supplied for each band). If more than one
107 value is supplied all values should be quoted to keep them together
108 as a single operating system argument. If the option is not
109 specified, instrinsic nodata settings on the first dataset will be
110 used (if they exist). The value set by this option is written in
111 the NoDataValue element of each VRTRasterBand element. Use a value
112 of None to ignore intrinsic nodata settings on the source datasets.
113 -separate:
115 (starting with GDAL 1.7.0) Place each input file into a separate
116 stacked band. In that case, only the first band of each dataset
117 will be placed into a new band. Contrary to the default mode, it is
118 not required that all bands have the same datatype.
119 -allow_projection_difference:
121 (starting with GDAL 1.7.0) When this option is specified, the
122 utility will accept to make a VRT even if the input datasets have
123 not the same projection. Note: this does not mean that they will be
124 reprojected. Their projection will just be ignored.
125 -input_file_list:
127 To specify a text file with an input filename on each line
128 -q:
130 (starting with GDAL 1.7.0) To disable the progress bar on the
131 console
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134 gdalbuildvrt doq_index.vrt doq/*.tif
135 gdalbuildvrt -input_file_list my_liste.txt doq_index.vrt
136 gdalbuildvrt -separate rgb.vrt red.tif green.tif blue.tif
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139 Even Rouault <even.rouault@mines-paris.org>
140GDAL Fri Apr 22 2011 gdalbuildvrt(1)