ras_formats man page

ras_formats — Information on raster formats supported by NCAR Graphics and NCAR View.

Synopsis

Abekas A60, AVS, Generic Binary, HDF, HPPCL, NRIF, Sun, SGI, and XWD.

Description

NCAR Graphics and NCAR View applications are built upon a common library that provides read and write access to raster imagery. The table below summarizes the support that is provided for all the different formats. Note that a format may be writeable but not readable, and that a compressed image may be readable but not writeable. By default, a raster image is written as compressed if possible. For those applications that key upon the filename to determine the raster format, or allow a -ifmt or -ofmt, the extension, as listed below, should be used without the "." in front (e.g. use "hdf", not ".hdf").

Format(extensions)EncodingInputOutputCompression
Abekas A60(.a60)RGB24YesYesNone
AVS(.avs)RGB24YesYesNone
HDF(.hdf)Indexed-8YesYesIn/Out
HDF(.hdf)Direct-24YesYesIn/Out
HPPCL(.hppcl)Indexed-8NoYesOut
NRIF(.nrif)BilevelNoNoNone
NRIF(.nrif)Indexed-8YesYesIn/Out
NRIF(.nrif)Direct-24YesYesIn/Out
Sun(.sun)Indexed-8YesYesIn
Sun(.sun)Direct-24YesNoIn
SGI(.sgi,.rgb)Direct-24YesYesIn
XWD(.xwd)Indexed-8YesYesNone

Caveats

Not all formats and encodings that are supported for output are supported for input; the software has separate input and output drivers for format/encoding pair.

For all the formats listed below, only 8-bit pixels and 8-bit run-lengths (where applicable) are supported.

Experience with HDF's "advanced" compression option indicates that you should use it only if you consider random pixels an advanced-appearing image.

See Also

rasview(1NCARG), rasls(1NCARG), rascat(1NCARG), rasgetpal(1NCARG), rassplit(1NCARG)

Hardcopy: NCAR Graphics Fundamentals, UNIX Version

Info

February 1993 NCAR NCAR VIEW