NAME

       pamcut - cut a rectangle out of a PAM, PBM, PGM, or PPM image

SYNOPSIS

       pamcut

       [-left colnum]

       [-right colnum]

       [-top rownum]

       [-bottom rownum]

       [-width cols]

       [-height rows]

       [-pad]

       [-cropleft numcols]

       [-cropright numcols]

       [-croptop numrows]

       [-cropbottom numrows]

       [-verbose]

       [left top width height]

       [pnmfile]

       Minimum  unique  abbreviations  of  option  are acceptable.  You may use double hyphens instead of single
       hyphen to denote options.  You may use white space in place of the equals sign to separate an option name
       from its value.

DESCRIPTION

       This program is part of Netpbm(1).

       pamcut reads a PAM, PBM, PGM, or PPM image as input and extracts the specified  rectangle,  and  produces
       the same kind of image as output.

       You can specify either the rectangle to cut out and keep or specify the edges to crop off and discard, or
       a combination.

       To request edges be cropped off, use options -cropleft, -cropright, -croptop, and -cropbottom to indicate
       how many rows or columns to discard.

       For example, -cropleft=50 -cropright=200 means to discard the leftmost 50 and rightmost 200 columns.

       To specify the rectangle to keep, use -left, -right, -top, -bottom, -width, -height, and -pad options.

       For example, -left=50 -right=200 means to keep the 150 columns between Columns 50 and 200 inclusive.

       You  can  code any mixture of the options.  What you don't specify defaults.  Those defaults are in favor
       of minimal cutting and in favor of  cutting  the  right  and  bottom  edges  off.   It  is  an  error  to
       overspecify,  i.e.  to  specify  all  three of -left, -right, and -width or -top, -bottom, and -height or
       right as well as -cropright.

       There is an older way to specify the rectangle to keep: positional arguments.  Arguments  were  the  only
       way  available  before July 2000, but you should not use them in new applications.  Options are easier to
       remember and read, more expressive, and allow you to use defaults.

       If you use both options and arguments, the two specifications get mixed in an unspecified way.

       To use arguments, specify all four of the left, top, width, and height arguments.  left and top have  the
       same effect as specifying them as the argument of a -left or -top option, respectively.  width and height
       have  the  same  effect  as  specifying them as the argument of a -width or -height option, respectively,
       where they are positive.  Where they are not positive, they have the same effect as specifying  one  less
       than  the  value  as the argument to a -right or -bottom option, respectively.  (E.g. width = 0 makes the
       cut go all the way to the right edge).  Before July 2000, negative numbers were not allowed for width and
       height.

       Input is from Standard Input if you don't specify the input file pnmfile.

       Output is to Standard Output.

       pamcut works on a multi-image stream.  It cuts each image in the  stream  independently  and  produces  a
       multi-image  stream  output.  Before Netpbm 10.32 (March 2006), it ignored all but the first image in the
       stream.

       If you are splitting a single image into multiple same-size images, pamdice is  faster  and  easier  than
       running pamcut multiple times.

       pamcomp is also useful for cutting and padding an image to a certain size.  You create a background image
       of the desired frame dimensions and overlay the subject image on it.

OPTIONS

       In  addition  to  the options common to all programs based on libnetpbm (most notably -quiet, see  Common
       Options ), pamcut recognizes the following command line options:

       -left=colnum
              The column number of the leftmost column to be in the output.  Columns left of this get  cut  out.
              If  a  nonnegative  number,  it  refers  to columns numbered from 0 at the left, increasing to the
              right.  If negative, it refers to columns numbered -1 at the right, decreasing to the left.

       -right=colnum
              The column number of the rightmost column to be in the output, numbered the  same  as  for  -left.
              Columns to the right of this get cut out.

       -top=rownum
              The  row  number  of  the  topmost  row  to  be in the output.  Rows above this get cut out.  If a
              nonnegative number it refers to rows  numbered  from  0  at  the  top,  increasing  downward.   If
              negative, it refers to columns numbered -1 at the bottom, decreasing upward.

       -bottom=rownum
              The  row  number  of the bottom-most row to be in the output, numbered the same as for -top.  Rows
              below this get cut out.

       -width=cols
              The number of columns to be in the output.  Must be positive.

       -height=rows
              The number of rows to be in the output.  Must be positive.

       -cropleft

       -cropright

       -croptop

       -cropbottom
              These options tell how many rows or columns to crop from the left, right, top,  or  bottom  edges,
              respectively.

              The value must not be negative.

              These  option  were  new  in  Netpbm 10.85 (December 2018).  Before that, you can achieve the same
              thing with -left, top, and negative values for -right and -bottom.  Remember to  subtract  one  in
              the latter case; e.g. the equivalent of -cropright=1 is -right=-2.

       -pad   If  the rectangle you specify is not entirely within the input image, pamcut fails unless you also
              specify -pad.  In that case, it pads the output with black up to the edges you specify.   You  can
              use  this option if you need to have an image of certain dimensions and have an image of arbitrary
              dimensions.

              pnmpad also adds borders to an image, but you specify their width directly.

              pamcomp does a more general form of  this  padding.   Create  a  background  image  of  the  frame
              dimensions  and overlay the subject image on it.  You can use options to have the subject image in
              the center of the frame or against any edge and make the padding any color (the padding  color  is
              the color of the background image).

       -verbose
              Print information about the processing to Standard Error.

SEE ALSO

       pnmcrop(1), pamdice(1), pamcomp(1), pnmpad(1), pamcat(1), pgmslice(1), pnm(1)

HISTORY

       pamcut was derived from pnmcut in Netpbm 9.20 (May 2001).  It was the first Netpbm program adapted to the
       new PAM format and programming library.

       The predecessor pnmcut was one of the oldest tools in the Netpbm package.

AUTHOR

       Copyright (C) 1989 by Jef Poskanzer.

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/pamcut.html

netpbm documentation                             04 October 2019                           Pamcut User Manual(1)