dwww Home | Manual pages | Find package

Jbigtopnm User Manual(1)    General Commands Manual    Jbigtopnm User Manual(1)

NAME
       jbigtopnm - JBIG to PNM image file converter

SYNOPSIS
       jbigtopnm  [-xmax]  [-ymax]  [-binary]  [-diagnose] [-plane] [input-file
       [output-file]]

       Minimum unique abbreviation of option is 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).

       jbigtopnm reads a JBIG bi-level image entity (BIE) from a file or  stan-
       dard  input, decompresses it, and outputs a PBM or PGM file.  If the in-
       put has one plane, or you choose just one plane of  it,  the  output  is
       PBM.  Otherwise, the output is PGM.

       JBIG  is  a highly effective lossless compression algorithm for bi-level
       images (one bit per pixel), which is particularly suitable  for  scanned
       document pages.

       A JBIG encoded image can be stored in several resolutions in one or sev-
       eral  BIEs. All resolution layers except the lowest one are stored effi-
       ciently as differences to the next lower resolution layer.  You can  use
       options  -x and -y to stop the decompression at a specified maximal out-
       put image size.  The input file can consist of several concatenated BIEs
       which contain different increasing resolution layers of the same image.

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

       Before Netpbm 10.85 (December 2018), only single-character single-hyphen
       abbreviations of the options are accepted.

       -xmax number
              Decode only up to the largest resolution layer which is still not
              more than number pixels wide.  If no such  resolution  layer  ex-
              ists, then use the smallest one available.

       -ymax number
              Decode only up to the largest resolution layer which is still not
              more  than  number  pixels high.  If no such resolution layer ex-
              ists, then use the smallest one available.  You can also use  op-
              tions  -x  and  -y  together which selects the largest layer that
              satisfies both limits.

       -binary
              Use binary values instead of Gray code words in order  to  decode
              pixel  values  from  multiple  bitplanes.  This option has effect
              only if the input has more than one bitplane and you don't select
              just one of those bitplanes.  Note that the  decoder  has  to  be
              used  in  the  same mode as the encoder and cannot determine from
              the BIE, whether Gray or binary code words were used by  the  en-
              coder.

       -diagnose
              Diagnose  a  BIE.  With this option, jbigtopnm only prints a sum-
              mary of the header information found in the input file  and  then
              exits.

       -plane number
              If  the  input contains multiple bitplanes, then extract only the
              specified single plane as a PBM file.  The first plane has number
              0.

STANDARDS
       This program implements the JBIG image coding algorithm as specified  in
       ISO/IEC 11544:1993 and ITU-T T.82(1993).

AUTHOR
       jbigtopnm is based on the JBIG library by Markus Kuhn, part of his ]8;;http://www.cl.cam.ac.uk/~mgk25/jbigkit/\JBIG-
       KIT package]8;;\ .  The jbgtopbm program is part of the JBIG-KIT package.

       jbigtopnm is part of the Netpbm package of graphics tools.

SEE ALSO
       pnm(1), pnmtojbig(1)

LICENSE
       There  was at one time concern about the need for patent licenses to use
       jbigtopnm, but any relevant patents expired by 2012.

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/jbigtopnm.html

netpbm documentation              28 July 2020         Jbigtopnm User Manual(1)

Generated by dwww version 1.16 on Tue Dec 16 06:36:28 CET 2025.