#!/bin/bash # # Developed by Fred Weinhaus 3/31/2012 .......... 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: sigmoidal [-b bri] [-c con] [-C channels] [-l lutlength] [-g] infile outfile # USAGE: sigmoidal [-h or -help] # # OPTIONS: # # -b bri brightness change; float; positive increases brightness; # negative decreases brightness; default=0 (no change) # -c con contrast change; float; positive increases contrast; # negative decreases contrast; default=0 (no change) # -C channels any valid IM combination of channels corresponding to # the image's colorspace to which to apply the # transformation: r,g,b,a, or c,m,y,k,a; # default=all non-alpha channels # -l lutlength length of 1D lut; integer>0; default=1000 # -g enables the creation of a graph of the sigmoidal curve # mapping transformation, which is then displayed # automatically. There is a default setting below that # can be changed to enable this to be save to a file # named outfile_sigmoidal_graph.gif rather than just viewed. # ### # # NAME: SIGMOIDAL # # PURPOSE: To apply a sigmoidal brightness and/or contrast adjustment to an image. # # DESCRIPTION: SIGMOIDAL applies a sigmoidal brightness and/or contrast # adjustment to an image. The contrast change is the IM # -/+sigmoidal-contrast con,50%. The brightness change is the IM # -/+sigmoidal-contrast bri,0%. Thus it is half the sigmoidal curve. # The bri values are 10 time larger than those used in the IM function and # the con values are 5 time larger than those used in the IM function. # The transformation is generated as a 1D lut and applied to the image using # -clut to affect the desired brightness and/or contrast transformation. # The transformation is sensitive to the specified channels. This script is # similar to, but not exactly identical to the Photoshop new (CS3 or higher) # brightness contrast function. # # OPTIONS: # # -b bri ... BRI is the amount of brightness change. Values are positive or # negative floats. Positive values increase the brightness, while negative # values decrease the brightness. The default=0 for no change. # # -c con ... CON is the amount of contrast change. Values are positive or # negative floats. Positive values increase the contrast, while negative # values decrease the contrast. The default=0 for no change. # # -C channels ... CHANNELS are any valid IM combination of channels # corresponding to the image's colorspace to which to apply the transformation. # Combinations include: r,g,b,a, or c,m,y,k,a (with no commas). The # default=all non-alpha channels. # # -l lutlength ... LUTLENGTH is the length of 1D lut. Values are integer>0. # The default=1000. # # -g ... enables the creation of a graph of the knee curve mapping # transformation, which is then displayed automatically. There is a default # setting below that can be changed to enable this to be save to a file named # outfile_sigmoidal_graph.gif. The graph will be scaled to size 100x100. # # REQUIREMENTS: IM 6.3.5-7 is required to support the use of -clut # # NOTE: Negative values for con do not work properly between IM 6.7.6.4 and # IM 6.7.8.2 inclusive due to bug in +sigmoidal-contrast # # 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 value for scale and height of lut bri=0 # amount of brightness change; float con=0 # amount of contrast change; float channels="" # combination of channels: r,g,b,a or c,m,y,k,a lutlength=1000 # length of 1D lut # set flag if graph is permanent (graph=save) or temporary (graph=view) graph="view" # 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, usage and exit 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 11 ] 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 ;; -g) # display graph display_graph="yes" ;; -b) # get brightness amount shift # to get the next parameter # test if parameter starts with minus sign errorMsg="--- INVALID BRI SPECIFICATION ---" # checkMinus "$1" # test values bri=`expr "$1" : '\([-.0-9]*\)'` [ "$bri" = "" ] && errMsg "--- BRI=$bri MUST BE A FLOAT ---" ;; -c) # get contrast amount shift # to get the next parameter # test if parameter starts with minus sign errorMsg="--- INVALID CON SPECIFICATION ---" # checkMinus "$1" # test values con=`expr "$1" : '\([-.0-9]*\)'` [ "$con" = "" ] && errMsg "--- CON=$con MUST BE A FLOAT ---" ;; -l) # get lutlength shift # to get the next parameter # test if parameter starts with minus sign errorMsg="--- INVALID LUTLENGTH SPECIFICATION ---" checkMinus "$1" # test values lutlength=`expr "$1" : '\([0-9]*\)'` [ "$lutlength" = "" ] && errMsg "--- LUTLENGTH=$lutlength MUST BE AN INTEGER ---" testA=`echo "$amlutlengthount <= 0" | bc` [ $testA -eq 1 ] && errMsg "--- LUTLENGTH=$lutlength MUST BE A POSITIVE INTEGER ---" ;; -C) # get channels shift # to get the next parameter # test if parameter starts with minus sign errorMsg="--- INVALID CHANNELS SPECIFICATION ---" checkMinus "$1" # test values channels=`expr "$1" : '\([-rgbcmyka]\)'` [ "$channels" = "" ] && errMsg "--- CHANNELS=$channels MUST BE A COMBINATION OF R,G,B,A OR C,M,Y,K,A WITH NO COMMAS ---" ;; -) # 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 [ "$outfile" = "" ] && errMsg "--- NO OUTPUT FILE SPECIFIED ---" # setup temporary images and auto delete upon exit # use mpc/cache to hold input image temporarily in memory tmpI1="$dir/sigmoidal_I_$$.mpc" tmpI2="$dir/sigmoidal_I_$$.cache" tmpL1="$dir/sigmoidal_L_$$.mpc" tmpL2="$dir/sigmoidal_L_$$.cache" # get outfile name before suffix outname=`echo "$outfile" | sed -n 's/^\([^.]*\)[.][^.]*$/\1/ p'` gg="_sigmoidal_graph" graphfile="$outname$gg.gif" # delete temporaries trap "rm -f $tmpI1 $tmpI2 $tmpL1 $tmpL2;" 0 trap "rm -f $tmpI1 $tmpI2 $tmpL1 $tmpL2; exit 1" 1 2 3 15 trap "rm -f $tmpI1 $tmpI2 $tmpL1 $tmpL2; exit 1" ERR # read the input image into the temp files and test validity. convert -quiet "$infile" +repage "$tmpI1" || errMsg "--- FILE $infile1 DOES NOT EXIST OR IS NOT AN ORDINARY FILE, NOT READABLE OR HAS ZERO SIZE ---" # setup channels if [ "$channels" != "" ]; then channelize="-channel $channels" else channelize="" fi # scale bri and con to range used by IM -sigmoidal-contrast abri=`convert xc: -format "%[fx:(1/10)*abs($bri)]" info:` acon=`convert xc: -format "%[fx:(2/10)*abs($con)]" info:` #echo "abri=$abri; acon=$acon" # test abri and acon if zero, positive or negative # note values less than 0.0001 are essentially zero, but -sigmoidal-contrast fails at exactly zero britest=`convert xc: -format "%[fx:abs($abri)<0.0001?0:($bri>0?1:-1)]" info:` contest=`convert xc: -format "%[fx:abs($acon)<0.0001?0:($con>0?1:-1)]" info:` #echo "britest=$britest; contest=$contest;" # create gradient for base lut # colorspace RGB and sRGB swapped between 6.7.5.5 and 6.7.6.7 # though probably not resolved until the latter # then -colorspace gray changed to linear between 6.7.6.7 and 6.7.8.2 # then -separate converted to linear gray channels between 6.7.6.7 and 6.7.8.2, # then -gradients: had both linear an no-linear options between 6.7.6.7 and 6.7.8.3, # though much of the above probably not resolved until the latter # so change gradient to linear form with gray() rather than gray names # tested on 6.7.4.10, 6.7.6.10, 6.7.7.8 to 6.7.8.3 convert -size 1x$lutlength gradient:"gray(255)-gray(0)" -rotate 90 $tmpL1 # apply brightness and contrast using sigmoidal-contrast if [ $britest -eq 0 -a $contest -eq 1 ]; then # positive contrast only convert $tmpL1 $channelize -sigmoidal-contrast $acon,50% +channel $tmpL1 elif [ $britest -eq 0 -a $contest -eq -1 ]; then # negative contrast only convert $tmpL1 $channelize +sigmoidal-contrast $acon,50% +channel $tmpL1 elif [ $britest -eq 1 -a $contest -eq 0 ]; then # positive brightness only convert $tmpL1 $channelize -sigmoidal-contrast $abri,0% +channel $tmpL1 elif [ $britest -eq -1 -a $contest -eq 0 ]; then # negative brightness only convert $tmpL1 $channelize +sigmoidal-contrast $abri,0% +channel $tmpL1 elif [ $britest -eq 1 -a $contest -eq 1 ]; then # positive brightness and positive contrast convert $tmpL1 $channelize -sigmoidal-contrast $acon,50% -sigmoidal-contrast $abri,0% +channel $tmpL1 elif [ $britest -eq 1 -a $contest -eq -1 ]; then # positive brightness and negative contrast convert $tmpL1 $channelize +sigmoidal-contrast $acon,50% -sigmoidal-contrast $abri,0% +channel $tmpL1 elif [ $britest -eq -1 -a $contest -eq 1 ]; then # negative brightness and positive contrast convert $tmpL1 $channelize -sigmoidal-contrast $acon,50% +sigmoidal-contrast $abri,0% +channel $tmpL1 elif [ $britest -eq -1 -a $contest -eq -1 ]; then # negative brightness and negative contrast convert $tmpL1 $channelize +sigmoidal-contrast $acon,50% +sigmoidal-contrast $abri,0% +channel $tmpL1 fi # process output convert $tmpI1 $tmpL1 -clut "$outfile" # convert lut into text format and scale to 101x101 frac=`convert xc: -format "%[fx:101/255]" info:` pixvals=`convert $tmpL1 -scale "101x1!" -depth 8 -evaluate multiply $frac \ -compress none pgm:- | sed '1,3d'` # display graph if option -g if [ "$display_graph" = "yes" ];then # create point pair list plist="" x=0 for y in $pixvals; do plist="$plist $x,$y" x=$(($x+1)) done numpairs=$(($x-1)) # create and display graph # echo "Points = $plist" convert -size 150x150 xc: -fill white -stroke black \ -draw "rectangle 40,10 141,112" $tmpI1 convert $tmpI1 \ \( -size 100x101 xc: -stroke red -fill white -draw "polyline $plist" -flip \) \ -compose over -geometry 100x101+41+11 -composite $tmpI1 convert $tmpI1 -font Arial -pointsize 10 \ -draw "text 30,122 '0' text 20,17 '100' text 20,17 '100' text 40,60 '_' \ text 27,65 '50' text 90,112 '|' text 85,125 '50' text 70,140 'i n p u t'" $tmpI1 convert -respect-parenthesis $tmpI1 \ \( -background white -fill black -font Arial -pointsize 10 \ -gravity center label:'o \nu \nt \np \nu \nt ' -trim \) \ -geometry +10+20 -compose over -composite $tmpI1 if [ "$graph" = "view" ]; then convert $tmpI1 show: elif [ "$graph" = "save" ]; then convert $tmpI1 $graphfile fi fi exit 0