NAME

       pamhue - change a Netpbm image's hues

SYNOPSIS

       pamhue [-huechange=[degrees]] filename

       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).

       pamhue shifts the hue of every pixel in an image by the same amount.

       If the image is in a black and white or grayscale format, the image is fully desaturated, so the  hue  is
       meaningless and pamhue leaves the image unchanged.

       Hue-Saturation-Value,  or  HSV, is one way to represent a color, like the more well-known RGB.  Hue is an
       indication of the secondary color with the same brightness that most closely approximates the  color.   A
       secondary color is made of a combination of at most two of the primary colors.

       In the HSV model, hue is an angular position on the color wheel.

       With  pamhue, you indicate an angle by which to change all the hues in the image; for example you can say
       move it 60 degrees clockwise.  That would change all red pixels to yellow and all yellow pixels to green,
       etc.

       To modify the saturation and value components of the colors, use pambrighten.

EXAMPLES

       To shift the color of each pixel 120 degrees clockwise:
       pamhue -huechange=120

       To shift the color of each pixel 120 degrees counterclockwise:
       pamhue -huechange=-120

OPTIONS

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

       -huechange=degrees
              This  option  specifies  the  amount to shift each color.  It is in degrees, with positive meaning
              clockwise and negative meaning counterclockwise.  It may be fractional and may be more than a full
              revolution.

              This option is mandatory.

HISTORY

       pamhue was new in Netpbm 10.86 (March 2019).

SEE ALSO

       pambrighten(1), ppmflash(1), ppmhist(1), ppm(1)

AUTHOR

       Copyright (C) 2018 by Willem van Schaik.  Copyright (C) 1990 by Brian Moffet.  Copyright (C) 1989 by  Jef
       Poskanzer.

       Permission  to  use, copy, modify, and distribute this software and its documentation for any purpose and
       without fee is hereby granted, provided that the above copyright notice appear in  all  copies  and  that
       both  that copyright notice and this permission notice appear in supporting documentation.  This software
       is provided "as is" without express or implied warranty.

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/pamhue.html

netpbm documentation                             07 January 2018                           Pamhue User Manual(1)