CHIMGTYP (August,1997)        ftools.fimage       CHIMGTYP (August,1997)



NAME
    chimgtyp  -  Converts  (changes)  the data type (BITPIX) of an image
    array of the FITS image extension.
    
    
    
USAGE
    chimgtyp infile outfile datatype
    
    
DESCRIPTION
    CHIMGTYP converts the data type of the image  extension.  It  writes
    the  image  array  to  an output file with modified bitpix value and
    modified array values as requested by user.  The FITS  defined  data
    types are:
     ----------------------------------------------
     datatype   meaning                    bitpix
     ----------------------------------------------
     UBYTE       8-bit unsigned byte          8
     USHORT      unsigned short              16
     SHORT       signed short                16
     ULONG       unsigned long               32
     LONG        signed long                 32
     FLOAT       single precision float     -32
     DOUBLE      double precision float     -64
    
    
CAUTION:
    Note that certain convertions (e.g., float --> int, double -->
    float, long --> short, etc.) may cause loss of information.
    
    
PARAMETERS
    
    infile [string]
        The name of the input image file.
    
    outfile [string]
        The name of output file.
    
    datatype[string]
        Datatype to be converted to (e.g., USHORT, or LONG, etc.).
    
    (Fnull= -1e37)[float]
        Value to assign undefined floating point pixels for output
        file. This is used when datatype is FLOAT or DOUBLE.
    
    (Inull= -99)[int]
        Value to assign undefined integer pixels for output file. This
        is used when datatype is LONG, or SHORT. Possible limits of
        this value, for converting to various datatypes are:
        datatype            limits
        -------------------------------------
        UBYTE                  0 to 255
        USHORT                 0 to 65535
        SHORT             -32768 to +32767
        ULONG                  0 to 4294967295
        LONG         -2147483648 to 2147483647
        -------------------------------------
        
    
    (copyall= yes)[boolean]
        To copy all other existing extensions from the input file.  By
        default, it is set to value 1 (true) which means, the task will
        copy all other existing extensions from the input to output. To
        reverse this option, one needs to enter copyall=0 in the
        command line.
    
    (clobber = no) [boolean])
        Flag specifying whether or not a  pre-existing  file  with  the
        same  name  as that  requested as the output file from this task
        will be overwritten.
        
        
EXAMPLES
    
    1. To convert image type from DOUBLE to ULONG,
    
    prompt> chimgtyp infile outfile datatype=ULONG Inull=99
        
        
        
BUGS
    
    None Known
    
    
LOG OF SIGNIFICANT CHANGES
    
    V1.0.0 (1997 August)
    
    
PRIMARY AUTHOR
    
    Banashree M Seifert
    
    
CONTACT FOR PROBLEM
    
    http://heasarc.gsfc.nasa.gov/cgi-bin/ftoolshelp