vdcomp(1)

Name
       vdcomp - decompress a compressed PDS image

Synopsis
       vdcomp [ infile ] [ outfile ] [ format-code ]

Description
       The  vdcomp program reads a variable length compressed PDS
       image and outputs a fixed length uncompressed  image  file
       in  PDS  format  with labels, image histogram, engineering
       table, line header table and  an  image  with  PDS,  FITS,
       VICAR or no labels.

       If  used on a non-byte-swapped machine the image histogram
       is un-swapped.

Options
       Vdcomp will prompt for any options that are  not  supplied
       on the command-line.

       infile
              The name of compressed image file.

       outfile
              The name of uncompressed image file.

       format-code
              Select from the following list:
                     1 - SFDU/PDS format [default]
                     2 - FITS format
                     3 - VICAR format
                     4 - unlabelled binary array

Limitations
       This  program  has been tested on a VAX 780 (VMS 4.6), SUN
       Workstation (UNIX 4.2, release 3.4), an IBM PC  (MICROSOFT
       5.1 compiler) and Macintosh IIx using Lightspeed C version
       3.0.  When converting to other systems, check  for  porta-
       bility conflicts.

Credits
       This program uses Kris Becker's subroutine DECOMP.C (which
       is included in this program in a shortened version).

History
       bradley@cis.upenn.edu 06-23-94 ansi-fied program

       datri@convex.com, 11-15-91 added recognition of - as  std-
       out   for  output  filename;  disabled  various  messages;
       directed messages to stderr; added exit status

       DEC89 Modified program to handle both Voyager  and  Viking
       images.

       OCT89  Converted  Voyager  decompression program to handle
       Viking compressed images.  Changed obuf to  'unsigned'  to
       simplify computation of checksum.

       AUG89  Added  code to get command line arguments for file-
       names and output format; routines to free memory  used  by
       the Huffman tree); fixed the SFDU label output length; and
       modified the I/O routines so that the open for Host type 2
       uses binary I/O.

       JUN89  Fixed  READVAR,  to  get length on 16-bit unswapped
       hosts.

       JUL88 C driver to decompress standard  Voyager  Compressed
       images by Mike Martin 1989/12/02.