NAME

       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)   Encoding    Input   Output   Compression
       ──────────────────────────────────────────────────────────────

       Abekas A60(.a60)     RGB24        Yes     Yes        None
       AVS(.avs)            RGB24        Yes     Yes        None
       HDF(.hdf)            Indexed-8    Yes     Yes       In/Out
       HDF(.hdf)            Direct-24    Yes     Yes       In/Out
       HPPCL(.hppcl)        Indexed-8    No      Yes         Out
       NRIF(.nrif)          Bilevel      No       No        None
       NRIF(.nrif)          Indexed-8    Yes     Yes       In/Out
       NRIF(.nrif)          Direct-24    Yes     Yes       In/Out
       Sun(.sun)            Indexed-8    Yes     Yes         In
       Sun(.sun)            Direct-24    Yes      No         In
       SGI(.sgi,.rgb)       Direct-24    Yes     Yes         In
       XWD(.xwd)            Indexed-8    Yes     Yes        None

       ──────────────────────────────────────────────────────────────

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

COPYRIGHT

       Copyright (C) 1987-2009
       University Corporation for Atmospheric Research

       The use of this Software is governed by a License Agreement.

NCAR                                              February 1993                               RAS_FORMATS(1NCAR)