#!/bin/sh

# try-pngzop

# usage: try-pngzop dir ...

# runs pngzop on each PNG file in a set of directories

# For use in the pngzop project
# Copyright 2013 by Glenn Randers-Pehrson
# Released under the pngcrush license (equivalent to the libpng license)

# From a PNG file, finds the smallest resulting compressed IDAT
# data from zopfli compression of filter types 0 through 4 and
# "adaptive" (f5) filtering.

for dir in $*
do
(
    cd $dir
    for n in *.png
    do
        pngzop $n > $n.zop
        pngcrush -brute -force $n $n.bf.png
        pngzdat $n.bf.png
    done
)
done