NAME

       ppmflash - brighten a picture to approach white

SYNOPSIS

       ppmflash flashfactor [ppmfile]

DESCRIPTION

       This program is part of Netpbm(1).

       ppmflash  reads  a PPM image as input.  It changes the color of each pixel to bring it a specified amount
       closer to white.  It generates a PPM image of the result.

       flashfactor is a real number between 0 and 1, inclusive.  ppmflash increases the intensity  of  each  RGB
       component by the fraction flashfactor of the difference between the current value and full intensity.  So
       if  a  pixel  contains  60%  full  red,  10% full green, and no blue and you specify 0.5 (half), ppmflash
       increases the red to 80% (because it was 40% from full intensity, so it adds half of 40% to the  original
       60%), the green to 55%, and the blue to 50%.

       If  flashfactor  is zero, the output is identical to the input.  If flashfactor is one, the output is all
       white.

       pambrighten does a more normal kind of brightening.   pamfunc  does  a  very  simple  brightening.   Both
       pambrighten and pamfunc can reduce brightness as well.

       pnmgamma is another way people do a similar brightening, though it isn't really intended for that.

OPTIONS

       There are no command line options defined specifically for ppmflash, but it recognizes the options common
       to all programs based on libnetpbm (See  Common Options .)

SEE ALSO

       pambrighten(1) pamfunc(1), pnmgamma(1), ppm(1),

AUTHOR

       Copyright (C) 1993 by Frank Neumann

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/ppmflash.html

netpbm documentation                             26 January 2003                         Ppmflash User Manual(1)