#!/bin/bash
# 
# Developed by Fred Weinhaus 11/16/2007 .......... 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: colorboost [-f fact] infile outfile
# USAGE: colorboost [-h or -help]
# 
# OPTIONS:
# 
# -f      fact       color boost blending factor; 0<=integer<=100; default=0
# 
###
# 
# NAME: COLORBOOST
# 
# PURPOSE: To enhance the color in a under saturated image.
# 
# DESCRIPTION: COLORBOOST enhances the color in an under saturated image.
# It first creates an image that is the log of the ratio of the original 
# image to its grayscale version. This is then multiplied by the original 
# image to form a strongly color boosted image. Finally the original image 
# is blended with the strongly color boosted image to generate the output.
# 
# 
# OPTIONS: 
# 
# -f fact ... FACT specifies the color boost blending percentage. Values 
# for fact may be an integer between 0 and 100. A value of 0 indicates no 
# color boost. A value of 100 indicates full color boost. The default=0
# 
# Note: due to the use of -fx, this script may be a little slow.
#
# Reference: http://visl.technion.ac.il/1999/99-07/www/
# 
# 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
fact=0          # color boost blending factor

# 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 4 ]
	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
					   ;;
				-f)    # get fact for color boost
					   shift  # to get the next parameter - fact
					   # test if parameter starts with minus sign 
					   errorMsg="--- INVALID FACT SPECIFICATION ---"
					   checkMinus "$1"
					   # test fact values
					   fact=`expr "$1" : '\([0-9]*\)'`
					   [ "$fact" = "" ] && errMsg "FACT=$fact IS NOT A NON-NEGATIVE INTEGER"
		   			   facttestA=`echo "$fact < 0" | bc`
		   			   facttestB=`echo "$fact > 100" | bc`
					   [ $facttestA -eq 1 -o $facttestB -eq 1 ] && errMsg "--- FACT=$fact MUST BE GREATER THAN OR EQUAL 0 AND LESS THAN OR EQUAL 100 ---"
					   ;;
 				 -)    # STDIN, 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"

tmpA1="$dir/colorboost_1_$$.mpc"
tmpB1="$dir/colorboost_1_$$.cache"
tmpA2="$dir/colorboost_2_$$.mpc"
tmpB2="$dir/colorboost_2_$$.cache"
trap "rm -f $tmpA1 $tmpB1 $tmpA2 $tmpB2;" 0
trap "rm -f $tmpA1 $tmpB1 $tmpA2 $tmpB2; exit 1" 1 2 3 15
trap "rm -f $tmpA1 $tmpB1 $tmpA2 $tmpB2; exit 1" ERR

# get im version
im_version=`convert -list configure | \
	sed '/^LIB_VERSION_NUMBER */!d; s//,/;  s/,/,0/g;  s/,0*\([0-9][0-9]\)/\1/g' | head -n 1`

# colorspace RGB and sRGB swapped between 6.7.5.5 and 6.7.6.7 
# though probably not resolved until the latter
# then -colorspace gray changed to linear between 6.7.6.7 and 6.7.8.2 
# then -separate converted to linear gray channels between 6.7.6.7 and 6.7.8.2,
# though probably not resolved until the latter
# so -colorspace HSL/HSB -separate and -colorspace gray became linear
# but we need to use -set colorspace RGB before using them at appropriate times
# so that results stay as in original script
# Note that some -compose methods are not yet handling things properly, so have to add $setcspace
# Actually get better results by just adding $setcspace when converting infile to $tmpA
# The following was determined from various version tests using colorboost.
# with IM 6.7.4.10, 6.7.6.10, 6.7.8.7
if [ "$im_version" -lt "06070607" -o "$im_version" -gt "06070707" ]; then
	setcspace="-set colorspace RGB"
else
	setcspace=""
fi
# no need for setcspace for grayscale or channels after 6.8.5.4
# but to keep the same look, must use colorspace rec601luma via -intensity, since now colorspace gray is rec709luma
# also correct for -tint
if [ "$im_version" -gt "06080504" ]; then
	setcspace="-intensity rec601luma"
	graycorrect="-intensity rec601luma"
else
	graycorrect=""
fi


if convert -quiet "$infile" +repage $setcspace "$tmpA1"
	then
	: ' do nothing '
else
	errMsg "--- FILE $infile DOES NOT EXIST OR IS NOT AN ORDINARY FILE, NOT READABLE OR HAS ZERO SIZE ---"
fi

# save original
convert $tmpA1 $tmpA2

# create color boosted image image

convert $tmpA1 \( +clone $graycorrect -colorspace Gray \) -fx "log((u/max(v,.000001))+1)" $tmpA1
convert $tmpA1 $tmpA2 -compose multiply -composite -normalize $tmpA1

# blend color boosted image with original image
if [ "$im_version" -lt "06050304" ]; then
	composite -blend $fact% $tmpA $tmp0 "$outfile"
else
	convert $tmpA2 $tmpA1 -define compose:args=$fact% -compose blend -composite "$outfile"
fi

exit 0