NAME

       pnmindex - build a visual index of a bunch of PNM images

SYNOPSIS

       pnmindex

       [-size=N]

       [-across=N]

       [-black]

       [-title=title]

       [-quant|-noquant]

       [-colors=N]

       pnmfile ...

       You  can  use  the  minimum  unique  abbreviation of the options.  You can use two hyphens
       instead of one.  You can separate an option name from its value with white  space  instead
       of an equals sign.

DESCRIPTION

       This program is part of Netpbm(1).

       pnmindex  creates  an  index image containing thumbnail (small) versions of a bunch of PNM
       files you supply (akin to a photographic "contact sheet").

       pnmindex labels each thumbnail and, optionally, contains a title.

       If you just want to concatenate some images together in a grid, use pamundice for that.

       If you want to take apart the image you generated with pnmindex, use pamdice or pamcut.

       The program can generate large temporary files.  By default, these go in  directory  /tmp,
       but you can usse the TMPDIR environment variable to have them somewhere else.

OPTIONS

       In addition to the options common to all programs based on libnetpbm (most notably -quiet,
       see
        Common Options ⟨index.html#commonoptions⟩ ), pnmindex recognizes  the  following  command
       line options:

       -size=N
              The size of each thumbnail.  The image is scaled down to fit maximally inside a N x
              N pixel box without changing its aspect ratio.

              If the input image is already smaller than this, its size remains the same  in  the
              output.

              The value must be at least 1.

              The default is 100.

       -across=N
              This is the number of thumbnails in each row.

              The value must be at least 1.

              The default is 6.

       -black This  controls  the color of the padding between the images; by default it is white
              and the labels are black lettering on  white  background,  but  the  -black  option
              reverses this.

       -title=title
              This specifies a title to be placed at the top of the image.

              The  title  value  must  be  in ASCII.  Characters that are not valid ASCII are not
              rendered.

              Default is no title.

       -noquant
              Disables color quantization.  By default, if any input image is  PPM,  the  program
              reduces the number of colors to the number of colors specified by -colors).

       -quant This option has no effect; it explicitly selects the default behavior of quantizing
              colors.  See -noquant.

       -colors=N
              The maximum number of colors allowed in the overall image.  If it  would  otherwise
              have  more  colors than these, pnmindex quantizes the result.  To reduce the effect
              of the colors in one  thumbnail  on  the  colors  used  for  another,  the  program
              quantizes colors to this number in each thumbnail independently, then quantizes the
              colors in each row of thumbnails to this number, then quantizes the colors  in  the
              entire output image to this number.

              This  value  is meaningless if you specify the -noquant option or if no input image
              is PPM.

              The default is 256.

HISTORY

       Before Netpbm 11.05 (December 2023), the Netpbm common option -plain was not implemented.

         .UN seealso

SEE ALSO

       pamscale(1), pamcat(1),  pbmtext(1),  pnmquant(1),  pamcut(1),  pamdice(1),  pamundice(1),
       pnmtile(1), pnm(1)

AUTHOR

       Copyright (C) 1991 by Jef Poskanzer.

       -title and -noquant added 2000 by John Heidemann.

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/pnmindex.html