Level 2 Help for GEN

NL

 NL  (integer)  specifies  the  size  of  the  image in the line
 direction.

 Default is 10.


NS

 NS  (integer)  specifies  the  size  of the image in the sample
 direction, i.e., the number of samples per line.

 Default is 10.


NB

 NB  (integer)  specifies  the  size  of  the  image in the band
 direction, or the number of image planes in the file.  The file
 size is NL x NS x NB pixels.

 Default is one.


OUT

 OUT  is the standard VICAR output filename.  It is a string of
 form   "name.type",where  "name"  is  a  string  of  up  to  39
 alphanumeric  characters,  starting  with  an  alphabetic,  and
 "type"   is  an  optional  string  of  up  to  39  alphanumeric
 characters.

 Default is GEN.


FORMAT

 This  parameter  specifies  the data format.  If it is omitted,
 BYTE (unsigned INTEGER*1) data is assumed.  The number of bytes below
 is typical for VAX and Sun-type architechtures; it may be different
 on other kinds of machines.

 Valid values are:

 BYTE:  one byte unsigned integer (0 -> 255) (INTEGER*1)
 HALF:  two byte signed integer (-32768 -> +32767) (INTEGER*2)
 FULL:  four byte signed integer (INTEGER*4)
 REAL:  four byte (single precision) floating point (REAL*4)
 DOUB:  eight byte (double precision) floating point (REAL*8)
 COMP:  two four-byte (single precision) floating point numbers,
        in the order (real,imaginary).
 In  addition,  in  order  to  maintain compatability with older
 versions,  REAL4  and REAL8 are allowed as alternatives to REAL
 and DOUB respectively.  REAL4 and REAL8 should not generally be
 used, however, as they are being phased out.


IVAL

 The  value  of  IVAL  (integer  or floating point) is the value
 assigned to the initial DN at line 1, sample 1, band 1.  For
 COMPlex data only, IVAL can have both a real and an imaginary part.
 Normally, only the first (real) value is given.

 Default is 0.0 (and 0.0 imaginary).


SINC

 The value of SINC (integer or floating point) is the horizontal
 increment,  i.e., on a given line in a given band:

 (sample i+1) = (sample i) + SINC.

 For COMPlex data only, SINC can have both a real and an imaginary part.
 Normally, only the first (real) value is given.

 Default is 1.0 (and 1.0 imaginary).


LINC

 The  value  of LINC (integer or floating point) is the vertical
 increment, i.e., for a given band:

 (line i+1, sample j) = (line i, sample j) + LINC.

 For COMPlex data only, LINC can have both a real and an imaginary part.
 Normally, only the first (real) value is given.

 Default is 1.0 (and 1.0 imaginary).


BINC

 The  value  of  BINC  is  used  as  an  increment  in  the BAND
 direction, so that

 (line i, sample j, band k+1) = (line i, sample j, band k) + BINC

 For COMPlex data only, BINC can have both a real and an imaginary part.
 Normally, only the first (real) value is given.

 Default is 1.0 (and 1.0 imaginary).


MODULO

 The  value  of  MODULO  (integer  or floating point) is used to
 limit  the  output  values.   The  grey level values are output
 modulo  MODULO.   (Default is MODULO = 256 for byte pictures, =
 2**16 for halfword, = 2**32 for fullword.)

 For COMPlex data only, MODULO can have both a real and an imaginary part.
 Normally, only the first (real) value is given.


FLAT

This keyword can be used to generate flat field images.  'BLACK yields the
same result as IVAL=0, LINC=0, SINC=0, BINC=0 (a black image).  'WHITE 
produces the same result as IVAL=255, LINC=0, SINC=0, BINC=0 (a white image
for byte data).


ORG

 ORG  indicates  the organization of the output file.  The valid
 values are:

 BSQ -- Band Sequential
 BIL -- Band Interleaved by Line
 BIP -- Band Interleaved by Pixel

 For more info, see the example on the following page.

 The default organization is BSQ.

 Example:

 Using GEN to generate an image file as follows,

 GEN A NL=3 NS=4 NB=3 IVAL=1 SINC=0 LINC=0 BINC=1 ,

 the  resultant  image  would  be  a  series  of  records  whose
 organization  would  depend  on the ORG keyword, and the result
 would be:
					123
	1111		1111		123
	1111		2222		123
	1111		3333		123
	2222		1111		123
 BSQ:	2222	BIL:	2222	BIP:	123
	2222		3333		123
	3333		1111		123
	3333		2222		123
	3333		3333		123
					123
					123