man percentblack (Commandes) - how much coverage is there in a given 8-bit grayscale PNG image.
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).