man > pamseq(1)

Pamseq User Manual(1)                  General Commands Manual                 Pamseq User Manual(1)

NAME
       pamseq - generate PAM image of a numerical sequence of tuple values


SYNOPSIS
       pamseq [-tupletype=tupletype] depth maxval [-min=n,n,...]  [-max=n,n,...]  [-step=n,n,...]

       All  options can be abbreviated to their shortest unique prefix.  You may use two hyphens in‐
       stead of one to designate an option.  You may use either white space or an  equals  sign  be‐
       tween an option name and its value.


DESCRIPTION
       This program is part of Netpbm(1).

       pamseq generates a PAM image of a specified depth and specified
         maxval that consists of a single row.  The row consists of tuples
         containing sample values in a numerical sequence.

       For example

           pamseq 1 4


         generates a 5 pixel wide image of 1 row with depth 1 tuples containing these
         samples, in order from left to right:

           0 1 2 3 4


         The following example uses depth 2:

           pamseq 2 2


         The resulting image is a 9 pixel wide image of 1 row with depth 2 containing
         these samples, in order from left to right;

           (0,0) (0,1) (0,2) (1,0) (1,1) (1,2) (2,0) (2,1) 2,2)


         You can choose the starting and ending sample values and the step for each
         plane:  Here is an example of that:

           pamseq 1 255 -min=4 -max=8 -step=2


       This generates

           4 6 8


       In two dimensions:

           pamseq 2 255 -min=0,4 -max=2,8 -step=1,2


           (0,4) (0,6) (0,8) (1,4) (1,6) (1,8) (2,4) (2,6) (2,8)


         pamseq varies first the highest numbered plane, then the next lower
         numbered plane, etc.  Within each plane, the program varies from low sample
         value to high.



OPTIONS
       In  addition  to  the options common to all programs based on libnetpbm (most notably -quiet,
       see ]8;;index.html#commonoptions\ Common Options]8;;\ ), pamseq recognizes the following command line options:



       -tupletype
              This is the value of the "tuple_type" attribute of the created PAM image.  It  can  be
              any string up to 255 characters.


       -min=n,n,...
                This gives the starting value for the sequence in each plane.  The number
                of comma-separated numbers must be equal to the number of planes in the
                image (its depth).  Each number must be a whole number no greater than
                the maxval of the image.  The first number is for Plane 0, the second for
                Plane 1, etc.

              The default is 0 in every plane.

              This option was new in Netpbm 10.99 (June 2022).


       -max=n,n,...

              This is analogous to -min, giving the ending value for the
                  sequence.

              Each value must be at least as great as the corresponding -min
                  value.

              The default is the maxval in every plane.

              This option was new in Netpbm 10.99 (June 2022).


       -step=n,n,...

              This is analogous to -min, giving the step value for the
                  sequence (difference between two consecutive numbers).

              Each value must be positive and no greater than the maxval.

              The default is 1.

              This option was new in Netpbm 10.99 (June 2022).




USAGE
       To create a simple ramp of the values 0..255, for input to various matrix calculations, try
         pamseq 1 255

       (Before pamseq existed, pgmramp was often pressed into service for this).

       To create a PPM color map of all the possible colors representable with a maxval of 5, do
         pamseq 3 5 -tupletype=RGB | pamtopnm


       Again, with a modern program based on the Netpbm library, you don't need the pamtopnm because
       a PAM RGB image is equivalent to a PPM image.

       You  can  use such a color map with pnmremap(1) to quantize the colors in an image.  With the
       maxval of 5 given in the example, you get a color map of the set of "web safe" colors as  de‐
       fined by Netscape.  Most web browsers guarantee that they can produce at least these 216 col‐
       ors (215 plus black).

       pamrestack can often produce a useful two-dimensional image from pamseq's single row.

           pamseq 2 255 -min=0,4 -max=2,8 -step=1,2 | pamrestack -width=3


           (0,4) (0,6) (0,8)
           (1,4) (1,6) (1,8)
           (2,4) (2,6) (2,8)





SEE ALSO
       pnmremap(1), pamtopnm(1), pamrestack(1), pam(1)


HISTORY
       pamseq was added to Netpbm in June 2002.

DOCUMENT SOURCE
       This  manual  page  was  generated by the Netpbm tool 'makeman' from HTML source.  The master
       documentation is at

              http://netpbm.sourceforge.net/doc/pamseq.html

netpbm documentation                        30 April 2022                      Pamseq User Manual(1)