Help for PIC2VIC

Converts PIC formatted images to VICAR.  PIC is a trivially simple file format
used by the Robotics Group at JPL.  It consists of a 4-byte header with lines
and samples followed by image data.

PIC does not seem to support multi-band data.  However, the FIDO rover at
least uses it that way.  The BAND parameter can be used to select a band to
read.  No check is made that the band is present.  Data for each band simply
follows each other in the file with no intervening header.  There is also
no header to specify the number of bands (which is why it's not checked).

REVISION HISTORY
Date:                   March 18,1994
Cognizant Engineer:     S.V.Hwan
References:             PIC software, Todd Litwin, February 1993,
                        Caltech copyright (C) 1993
Modifications:
  1994-07-22 SVH - Moved PICS related routines to seperate file
  1994-09-05 MSTP - S/W Conversion (VICAR Porting)
  2000-09-28 RGD - Added BAND parameter
  2001-05-15 AXC - Modified pic_read.c routine to process multiband image
             on VMS system (AR-105427)
  2019-06-14 WLB - IDS-7924 - Fixed format directives
             Cleaned up misc. warnings
  2019-09-06 WLB - IDS-7922 - Initialized some variables.

PARAMETERS: