#!/bin/bash
#
# Developed by Fred Weinhaus 9/28/2012 .......... revised 4/25/2015
#
# ------------------------------------------------------------------------------
# 
# Licensing:
# 
# Copyright © Fred Weinhaus
# 
# My scripts are available free of charge for non-commercial use, ONLY.
# 
# For use of my scripts in commercial (for-profit) environments or 
# non-free applications, please contact me (Fred Weinhaus) for 
# licensing arrangements. My email address is fmw at alink dot net.
# 
# If you: 1) redistribute, 2) incorporate any of these scripts into other 
# free applications or 3) reprogram them in another scripting language, 
# then you must contact me for permission, especially if the result might 
# be used in a commercial or for-profit environment.
# 
# My scripts are also subject, in a subordinate manner, to the ImageMagick 
# license, which can be found at: http://www.imagemagick.org/script/license.php
# 
# ------------------------------------------------------------------------------
# 
####
#
# USAGE: ortoneffect [-b blur] [-o opacity] infile outfile
# USAGE: ortoneffect [-h or -help]
# 
# OPTIONS:
# 
# -b     blur         blur amount; float>=0; default=10
# -o     opacity      opacity; 0<=integer<=100; default=100
# 
###
# 
# NAME: ORTONEFFECT 
# 
# PURPOSE: To apply an Orton effect to an image.
# 
# DESCRIPTION: ORTONEFFECT applies an Orton (sandwich) effect to an image.
# 
# 
# ARGUMENTS: 
# 
# -b blur ... BLUR is the amount of blur. Values are floats>=0. The default=10.
# 
# -o opacity ... OPACITY percent. Values are integers betwee 0 and 100. 
# The default=100.
# 
# REFERENCES:
# http://www.bernskiold.com/2011/06/06/applying-orton-effect-photos/
# http://peterh111.wordpress.com/2010/12/11/the-easy-guide-to-creating-the-orton-effect/
# http://pcin.net/update/2006/11/01/the-orton-effect-digital-photography-tip-of-the-week/
# 
# CAVEAT: No guarantee that this script will work on all platforms, 
# nor that trapping of inconsistent parameters is complete and 
# foolproof. Use At Your Own Risk. 
# 
######
# 

# set default values
blur=10			# blur amount
opacity=100		# opacity

# set directory for temporary files
dir="."    # suggestions are dir="." or dir="/tmp"

# set up functions to report Usage and Usage with Description
PROGNAME=`type $0 | awk '{print $3}'`  # search for executable on path
PROGDIR=`dirname $PROGNAME`            # extract directory of program
PROGNAME=`basename $PROGNAME`          # base name of program
usage1() 
	{
	echo >&2 ""
	echo >&2 "$PROGNAME:" "$@"
	sed >&2 -e '1,/^####/d;  /^###/g;  /^#/!q;  s/^#//;  s/^ //;  4,$p' "$PROGDIR/$PROGNAME"
	}
usage2() 
	{
	echo >&2 ""
	echo >&2 "$PROGNAME:" "$@"
	sed >&2 -e '1,/^####/d;  /^######/g;  /^#/!q;  s/^#*//;  s/^ //;  4,$p' "$PROGDIR/$PROGNAME"
	}


# function to report error messages
errMsg()
	{
	echo ""
	echo $1
	echo ""
	usage1
	exit 1
	}


# function to test for minus at start of value of second part of option 1 or 2
checkMinus()
	{
	test=`echo "$1" | grep -c '^-.*$'`   # returns 1 if match; 0 otherwise
    [ $test -eq 1 ] && errMsg "$errorMsg"
	}

# test for correct number of arguments and get values
if [ $# -eq 0 ]
	then
	# help information
   echo ""
   usage2
   exit 0
elif [ $# -gt 6 ]
	then
	errMsg "--- TOO MANY ARGUMENTS WERE PROVIDED ---"
else
	while [ $# -gt 0 ]
		do
			# get parameter values
			case "$1" in
		  -h|-help)    # help information
					   echo ""
					   usage2
					   exit 0
					   ;;
				-b)    # get blur
					   shift  # to get the next parameter
					   # test if parameter starts with minus sign 
					   errorMsg="--- INVALID BLUR SPECIFICATION ---"
					   checkMinus "$1"
					   blur=`expr "$1" : '\([.0-9]*\)'`
					   [ "$blur" = "" ] && errMsg "--- BLUR=$blur MUST BE A NON-NEGATIVE FLOAT VALUE (with no sign) ---"
					   ;;
				-o)    # get opacity
					   shift  # to get the next parameter
					   # test if parameter starts with minus sign 
					   errorMsg="--- INVALID OPACITY SPECIFICATION ---"
					   checkMinus "$1"
					   opacity=`expr "$1" : '\([0-9]*\)'`
					   [ "$opacity" = "" ] && errMsg "--- OPACITY=$opacity MUST BE A NON-NEGATIVE INTEGER VALUE (with no sign) ---"
					   test1=`echo "$opacity < 0" | bc`
					   test2=`echo "$opacity > 100" | bc`
					   [ $test1 -eq 1 -o $test2 -eq 1 ] && errMsg "--- OPACITY=$opacity MUST BE AN INTEGER BETWEEN 0 AND 100 ---"
					   ;;
				 -)    # STDIN and end of arguments
					   break
					   ;;
				-*)    # any other - argument
					   errMsg "--- UNKNOWN OPTION ---"
					   ;;
		     	 *)    # end of arguments
					   break
					   ;;
			esac
			shift   # next option
	done
	#
	# get infile and outfile
	infile="$1"
	outfile="$2"
fi

# test that infile provided
[ "$infile" = "" ] && errMsg "NO INPUT FILE SPECIFIED"

# test that outfile provided
[ "$outfile" = "" ] && errMsg "NO OUTPUT FILE SPECIFIED"

# setup temp files
tmpA1="$dir/ortoneffect_1_$$.mpc"
tmpB1="$dir/ortoneffect_1_$$.cache"
trap "rm -f $tmpA1 $tmpB1;" 0
trap "rm -f $tmpA1 $tmpB1; exit 1" 1 2 3 15
trap "rm -f $tmpA1 $tmpB1; exit 1" ERR

# read and test image
convert -quiet "$infile" +repage "$tmpA1" ||
	echo  "--- FILE $infile DOES NOT EXIST OR IS NOT AN ORDINARY FILE, NOT READABLE OR HAS ZERO SIZE  ---"

#Process Image
# screen composite the image with itself
# blur a copy of the screen composite image and adjust its opacity
# delete the original and multiply composite the screen and blurred screen composite images
convert $tmpA1 \
\( -clone 0 -clone 0 -compose screen -composite -alpha set \) \
\( -clone 1 -blur 0x$blur -alpha set -channel a -evaluate set $opacity% +channel \) \
-delete 0 -compose multiply -composite \
"$outfile"

exit 0