📄 frmt_grass.html
字号:
<html><head><title>GRASS -- GRASS Rasters</title></head><body bgcolor="#ffffff"><h1>GRASS -- GRASS Rasters</h1>GDAL optionally supports reading of existing GRASS raster layers (cells, andimage groups), but not writing or export. The support for GRASS raster layers is determined when the library is configured, and requires libgrassto be pre-installed (see Notes below). <p>GRASS rasters can be selected in several ways.<p><ol><li> The full path to the cellhd file for the cell can be specified. Thisis not a relative path, or at least it must contain all the path componentswithin the database including the database root itself. The followingexample opens the cell "proj_tm" within the mapset "PERMANENT" of thelocation "proj_tm" in the grass database located at /u/data/grassdb.<p>eg.<br><pre> % gdalinfo /u/data/grassdb/proj_tm/PERMANENT/cellhd/proj_tm</pre><li> The full path to the directory containing information about an imagerygroup (or the REF file within it) can be specified to refer to the wholegroup as a single dataset. The following examples do the same thing.<p>eg.<br><pre> % gdalinfo /usr2/data/grassdb/imagery/raw/group/testmff/REF % gdalinfo /usr2/data/grassdb/imagery/raw/group/testmff</pre><li> If there is a correct .grassrc5setup in the users home directory then cells or imagery groups may be opened just by the cell name. This only works for cells or images in the current location and mapset as defined in the .grassrc5 file. <p></ol>The following features are supported by the GDAL/GRASS link.<p><ul><li> Up to 256 entries from cell colormaps are read (0-255). <li> Compressed and uncompressed integer, floating point and double precisioncells are all supported. Integer cells are classified with a band type of"Byte" if the 1-byte per pixel format is used, or UInt16 if the two byteper pixel format is used. Otherwise integer cells are treated as UInt32.<li> Georeferencing information is properly read from GRASS.<li> An attempt is made to translate coordinate systems, but some conversionsmay be flawed, in particular in handling of datums and units.</ul>See Also:<p><ul><li> <a href="http://grass.itc.it/">GRASS GIS Home Page</a><li> <a href="http://home.gdal.org/projects/grass/">libgrass page</a></ul><hr><h2>NOTES on driver variations</h2>For GRASS 5.7 Radim Blazek has moved the driver to using the GRASSshared libraries directly instead of using libgrass. Currently (GDAL 1.2.2 and later)both version of the driver are available and can be configured using"--with-libgrass" for the libgrass variant or "--with-grass=<dir>" for the new GRASS 5.7 library based version. The GRASS 5.7 driver version is currentlynot supporting coordinate system access, though it is hoped that will becorrected at some point.<p></body></html>
⌨️ 快捷键说明
复制代码
Ctrl + C
搜索代码
Ctrl + F
全屏模式
F11
切换主题
Ctrl + Shift + D
显示快捷键
?
增大字号
Ctrl + =
减小字号
Ctrl + -