## DESCRIPTION

r.in.gdal allows a user to create a (binary) GRASS raster map layer, or imagery group, from any GDAL supported raster file format, with an optional title. The imported file may also be optionally used to create a new location.

## OPTIONS

Extended explanations:

### Flags:

-e
  Extend the DEFAULT_WIND in PERMANENT mapset to include the region of the new map layer. Old resolution is preserved, but the region, and rows/cols are updated. This will fail if the user doesn't have write access to the PERMANENT mapset.

  ## GDAL supported raster formats

  Full details on GDAL supported formats are available at:

  http://www.gdal.org/formats_list.html

  Selected formats of more than 40 supported formats:

  Long Format Name | Code | Creation | Georeferencing | Maximum file size
  --- | --- | --- | --- | ---
  Arc/Info ASCII Grid | AAIGrid | Yes | Yes | No limits
  Arc/Info Binary Grid (.adf) | AIG | No | Yes | --
  AIRSAR Polarimetric | AIRSAR | No | No | --
  Microsoft Windows Device Independent Bitmap (.bmp) | BMP | Yes | Yes | 4GiB
  BSB Nautical Chart Format (.kap) | BSB | No | Yes | --
  VTP Binary Terrain Format (.bt) | BT | Yes | Yes | --
  CEOS (Spot for instance) | CEOS | No | No | --
  First Generation USGS DOQ (.doq) | DOQ1 | No | Yes | --
  New Labelled USGS DOQ (.doq) | DOQ2 | No | Yes | --
  Military Elevation Data (.dt0, .dt1) | DTED | No | Yes | --
  ERMapper Compressed Wavelets (.ecw) | ECW | Yes | Yes |
  ESRI .hdr Labelled | EHdr | No | Yes | --
  ENVI .hdr Labelled Raster | ENVI | Yes | Yes | No limits
  Envisat Image Product (.n1) | Envisat | No | No | --
  EOSAT FAST Format | FAST | No | Yes | --
  FITS (.fits) | FITS | Yes | No |
  Graphics Interchange Format (.gif) | GIF | Yes | No | 2GB
  Arc/Info Binary Grid (.adf) | GIO | Yes | Yes |
  GRASS Rasters | GRASS | No | Yes | --
  TIFF / GeoTIFF (.tif) | GTiff | Yes | Yes | 4GiB
  Hierarchical Data Format Release 4 (HDF4) | HDF4 | Yes | Yes | 2GiB
  Erdas Imagine (.img) | HFA | Yes | Yes | No limits
  Atlantis MFF2e | HKV | Yes | Yes | No limits
  Image Display and Analysis (WinDisp) | IDA | Yes | Yes | 2GB
  ILWIS Raster Map (.mpr,.mpl) | ILWIS | Yes | Yes | --
  Japanese DEM (.mem) | JDEM | No | Yes | --
  JPEG JFIF (.jpg) | JPEG | Yes | Yes | 4GiB (max dimentions 65500x65500)
  JPEG2000 (.jp2, .j2k) | JPEG2000 | Yes | Yes | 2GiB
  JPEG2000 (.jp2, .j2k) | JP2KAK | Yes | Yes | No limits
  NOAA Polar Orbiter Level 1b Data Set (AVHRR) | L1B | No | Yes | --
  Erdas 7.x .LAN and .GIS | LAN | No | Yes | 2GB
  In Memory Raster | MEM | Yes | Yes | 2GiB
  Atlantis MFF | MFF | Yes | Yes | No limits
  Multi-resolution Seamless Image Database | MrSID | No | Yes | --
  NDF | NLAPS Data Format | No | Yes | No limits
  NITF | NITF | Yes | Yes |
  NetCDF | netCDF | Yes | Yes | 2GB
  OGDI Bridge | OGDI | No | Yes | --
  PCI .aux Labelled | PAux | Yes | No | No limits
  PCI Geomatics Database File | PCIDSK | Yes | Yes | No limits
  Portable Network Graphics (.png) | PNG | Yes | No |
  PCRaster (.map) | PCRaster | Yes | No |
  Netpbm (.ppm,.pgm) | PNM | Yes | No | No limits
  RadarSat2 XML (product.xml) | RS2 | No | Yes | 4GB
  USGS SDTS DEM (*CATD.DDF) | SDTS | No | Yes | --
  SAR CEOS | SAR_CEOS | No | Yes | --
  USGS ASCII DEM (.dem) | USGSDEM | No | Yes | --
  X11 Pixmap (.xpm) | XPM | Yes | No |

  ## Location Creation

  r.in.gdal attempts to preserve projection information when importing datasets if the source format includes projection information, and if the GDAL driver supports it. If the projection of the source dataset does not match the projection of the current location r.in.gdal will report an error message (`Projection of dataset does not appear to match current location`) and then report the PROJ_INFO parameters of the source dataset.

  If the user wishes to ignore the difference between the apparent coordinate system of the source data and the current location, they may pass the -o flag to override the projection check.

  If the user wishes to import the data with the full projection definition, it is possible to have r.in.gdal automatically create a new location based on the projection and extents of the file being read. This is accomplished by passing the name to be used for the new location via the location parameter. Upon completion of the command, a new location will have been created (with only a PERMANENT mapset), and the raster will have been imported with the indicated output name into the PERMANENT mapset.

  Support for GCPs: In case the image contains GCPs they are written to a POINTS file within an imagery group. They can directly be used for i.rectify. The target option allows to automatically re-project the GCPs from their own projection into another projection read from the PROJ_INFO file of the location name target.

  ## NOTES

  I plan to make a variety of improvements to r.in.gdal in the future including support for reporting everything known about a dataset if the output parameter is not set.

  The r.in.gdal comand does support the following features, as long as the underlying format driver supports it:

  Color Table
    Bands with associated colortables will have the color tables transferred. Note that if the source has no colormap, r.in.gdal in GRASS 5.0 will emit no colormap. Use r.colors map=... color=grey to assign a greyscale colormap. In a future version of GRASS r.in.gdal will likely be upgraded to automatically emit greyscale colormaps.
  Data Types
    Most GDAL data types are supported. Float32 and Float64 type bands are translated as GRASS floating point cells (but not double precision ... this could be added if needed), and most other types are translated as GRASS integer cells. This includes 16bit integer data sources. Complex (some SAR signal data formats) data bands are translated to two floating point cell layers (*.real and *.imaginary).
  Georeferencing
    If the dataset has affine georeferencing information, this will be used to set the north, south, east and west edges. Rotational coefficients will be ignored, resulting in incorrect positioning for rotated datasets.
  Projection
    The datasets projection will be used to compare to the current location or to define a new location. Internally GDAL represents projections in OpenGIS Well Known Text format. A large subset of the total set of GRASS projections are supported.
  Null Values
    Raster bands for which a null value is recognised by GDAL will have the null pixels transformed into GRASS style nulls during import. Many generic formats (and formats poorly supported by GDAL) do not have a way of recognising null pixels in which case r.null should be used after the import.
  GCPs
    Datasets that have Ground Control Points will have them imported as a POINTS file associated with the imagery group. Datasets with only one band that would otherwise have been translated as a simple raster map will also have an associated imagery group if there are ground control points. The coordinate system of the ground control points is reported by r.in.gdal but not preserved. It is up to the user to ensure that the location established with i.target has a compatible coordinate system before using the points with i.rectify.

  ## EXAMPLES

  To import GLOBE DEM tiles (approx 1km resolution, better than GTOPO30 DEM data), the user has to download additionally the related HDR file(s). Finally, e.g. the 'terrain' color table can be assigned to the imported map with r.colors.

  ## NOTES

  "ERROR: Input map is rotated - cannot import."
  In this case the image must be first externally rotated, applying the rotation info stored in the metadata field of the raster image file. For example, the gdalwarp software can be used to transform the map to North-up.

  ## SEE ALSO

  r.colors, r.in.ascii, r.in.arc, r.in.bin, r.null

  ## REFERENCES

  GDAL Pages: http://www.gdal.org/

  ## AUTHOR

  Frank Warmerdam (email).

  Last changed: $Date: 2005/07/21 09:39:51 $