Provided by: printbill_4.1.2-1.1_i386 bug

NAME
       percentblack  -  how  much coverage is there in a given 8-bit grayscale
       PNG image.


SYNOPSIS
       percentblack filename.png


DESCRIPTION
       percentblack prints a percentage coverage for a  given  PNG  image,  to
       three decimal places.  filename.png must be 8-bit grayscale, such as is
       generated by GhostScript’s pnggray device. Pixels which are  gray  make
       an appropriately scaled contribution to the total percentage.


EXAMPLE
       percentblack filename.png

       yields

            4.462

       indicating that 4.462% of the page is covered in black.


REQUIREMENTS
       percentblack only requires libpng to be present on the system.


INSTALLATION
       Please  see  the accompanying README and INSTALL files for installation
       instructions.  Chances  are  if  you’re  reading  this  it’s  correctly
       installed.


AUTHORS
       printbill  and  the  accompanying  utilities  were  written  by  Daniel
       Franklin (d.franklin@ieee.org). The web interface was written  by  Phil
       Ciufo (phil@snrc.uow.edu.au).


AVAILABILITY
       You   can   always   grab   the   latest   and  greatest  version  from
       http://ieee.uow.edu.au/~daniel/software/printbill


SEE ALSO
       printbill(1),  printbill(8),   printbilld(1),   printbill_configure(8),
       printbill_grapher(1),   percentcolour(1),  percent_cmy(1),  pqcheck(1),
       printquote(1),   printbill_printer(1),   printbillrc(5),   printcap(5),
       init_from_passwd(8), pqm(8).