# pgmenhance - edge-enhance a PGM image - man(1) - [phpMan]

> **TLDR:** Edge-enhance a PGM image.
>
- Edge-enhance a PGM image:
  `pgmenhance {{path/to/image.pgm}} > {{path/to/output.pgm}}`
- Specify the level of enhancement:
  `pgmenhance -{{1..9}} {{path/to/image.pgm}} > {{path/to/output.pgm}}`

*Source: tldr-pages*

---

_Pgmenhance_ _User_ [_Manual_(1)](https://www.chedong.com/phpMan.php/man/Manual/1/markdown)              General Commands Manual             _Pgmenhance_ _User_ [_Manual_(1)](https://www.chedong.com/phpMan.php/man/Manual/1/markdown)

## NAME
       pgmenhance - edge-enhance a PGM image


## SYNOPSIS
### pgmenhance

       [-_N_]

       [_pgmfile_]


## DESCRIPTION
       This program is part of [**Netpbm**(1)](https://www.chedong.com/phpMan.php/man/Netpbm/1/markdown).

       **pgmenhance **reads a PGM image as input, enhances the edges, and writes a PGM image as output.

       The  edge enhancing technique is taken from Philip R. Thompson's "xim" program, which in turn
       took it from section 6 of "Digital Halftones by Dot Diffusion", D. E. Knuth, ACM  Transaction
       on  Graphics  Vol. 6, No. 4, October 1987, which in turn got it from two 1976 papers by J. F.
       Jarvis et. al.


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



### -_

              The  optional  **-_**N_  option should be a digit from 1 to 9.  1 is the lowest level of en‐
              hancement; 9 is the highest.  The default is 9.




## SEE ALSO
       [**pamedge**(1)](https://www.chedong.com/phpMan.php/man/pamedge/1/markdown), [**pgm**(1)](https://www.chedong.com/phpMan.php/man/pgm/1/markdown)


## 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/pgmenhance.html>**

netpbm documentation                       13 January 1989                 _Pgmenhance_ _User_ [_Manual_(1)](https://www.chedong.com/phpMan.php/man/Manual/1/markdown)