start _OPNG.exe *.png -zc9 -zm9 -zs3 -f0-5 -nc -strip "all"

@echo off
echo.
set apppath="F:OptiPNGOptiPNG.exe"
if [%1]==[] echo Usage: %0 "PNG Dir" && echo. && echo Error: Invalid parameters && goto :EOF
if not exist %1 echo Usage: %0 "PNG Dir" && echo. && echo Error: Invalid directory "%~1" && goto :EOF
%apppath% "%~1*.png" -zc9 -zm9 -zs3 -f0-5 -nc -strip "all"
for /d /r "%~1" %%a in (*.*) do %apppath% "%%~a*.png" -zc9 -zm9 -zs3 -f0-5 -nc -strip "all"