#!/bin/bash # # Developed by Fred Weinhaus 8/18/2007 .......... revised 2/9/2025 # # ------------------------------------------------------------------------------ # # 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: curves [-s xscale,yscale] [-c channel] [-g graphmode] "x1,y1 x2,y2 ..." infile outfile # USAGE: curves [-s xscale,yscale] [-c channel] [-g graphmode] -f point_file infile outfile # USAGE: curves [-h or -help] # # OPTIONS: # # "x1,y1 x2,y2 ..." break point values of piece-wise linear transformation # enclosed in quotes; minimum of one (x,y) break point pair; # x corresponds to the graylevel in the input image; # y corresponds to the graylevel in the outut image; # x,y non-negative floats enclosed in quotes; # list must be specified just prior to infile # -c channel channel to process; options are: red, green, blue, # lightness, brightness, luma and luminosity; # default=all rgb channels # -f point_file text file containing list of break points; # one x,y pair per line # -s xscale,yscale range of values for x,y breakpoint pairs from 0 to xscale,yscale; # positive integers; default=100,100 # -g graphmode enables the creation of a graph of the transformation # and optionally the original break point, which is then # displayed automatically. The choices are: curve (C) or # points (P), where the latter shows the original user # specified break points in addition to the curve. The # default is curve (C). There is a default setting below # that can be changed to enable this to be save to a file # named outfile_graph.gif # ### # # NAME: CURVES # # PURPOSE: To generate a smoothly interpolated, curved mapping look up table # from a set of break point and applies it to an image. # # DESCRIPTION: CURVES takes the supplied break point pairs and generates a # dimensional spline curve that is then used to create a 1-D look up table image. # The look up table image is then used to change grayscale values in the channels # of the input image. At least one point pair must be supplied either as an argument # or in a text file with one pair per line supplied. The x value is the position in the # look up table which is associated with the grayscale value of the desired channels of # the input image and the y value is the associated grayscale value for the corresponding # channels in the resulting output image. A Catmull-Rom spline is used to generate the # the curve and does go through the supplied point pairs. # # OPTIONS: # # "x1,y1 x2,y2" ... List of x,y break-points for the curved # transformation. The x,y values are non-negative break-point pairs for # the curved transformation. There is a minimum one point pair that must # be supplied. The x and y values are associated with the input and output # grayscale values of the look up table, where x,y values can range from 0 # to xscale,yscale. xscale determines the length of the 1D lookup table # (length=xscale + 1); that is, the range of x (input) values and yscale # determines the range of y (output) values. Both xscale and yscale must # be positive integers and their defaults are 100. If the first pair is # not 0,0 or the last pair is not xscale,yscale then those points will be # added automatically to the list of point pairs. IMPORTANT: the list of # break-point pairs must be specified just prior to infile outfile. # # -f point_file ... point-file is a text file containing the list of break # points, one x,y pair per line. # # -s xscale,yscale ... xscale,yscale is the range of values for the # x,y breakpoint pairs which go from 0 to xscale,yscale; positive # integers. The default is 100,100. Larger values for xscale and yscale # can be used for more accuracy. For example with xscale=yscale=100, x and # y values are specified between 0 and 100 and the length of the output # image is 101 pixels. For xscale=yscale=255, x and y values are specified # # between 0 and 255 and the length of the output image is 256. Equal # values for xscale and yscale are not required. # # -c channel ... CHANNEL to process. Options are: red, green, blue, lightness # (L from HSL), brightness (B from HSB), luma (Y from YCbCr) and luminosity # (L from Lab). The default=all rgb channels. # # -g graphmode... enables the creation of a graph of the curved transformation, # which is then displayed automatically. The choices are: curve (C) or # points (P), where the latter shows the original user specified break points # in addition to the curve. The default is no graph if this option is not used. # There is also a default setting below that can be changed to enable this to be # save to a file named outfile_graph.gif. The graph will be scaled to size 100x100. # IMPORTANT: To end the script, close/quit the graph image. # # REQUIREMENTS: IM 6.7.8.2 or higher when using channel=luminosity. # # 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 xscale=100 yscale=100 channel="" height=10 precision=1 # decimal precision pinc=1 # increment in pixels graphmode="" # initialization crad=2 # point circle radius # 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" } # function to test if valid positive float point pair testFloatPair() { v1=`echo $1 | cut -d, -f1` v2=`echo $1 | cut -d, -f2` test1=`expr "$v1" : '^[.0-9][.0-9]*$'` test2=`expr "$v2" : '^[.0-9][.0-9]*$'` [ $test1 -eq 0 -o $test2 -eq 0 ] && errMsg "$1 IS NOT A VALID POINT PAIR" [ `echo "scale=5; $v1>$xscale" | bc` -eq 1 ] && errMsg "--- XVALUE $v1 EXCEEDS ALLOWED RANGE ---" [ `echo "scale=5; $v2>$yscale" | bc` -eq 1 ] && errMsg "--- YVALUE $v1 EXCEEDS ALLOWED RANGE ---" } # test for correct number of arguments and get values if [ $# -eq 0 ] then # help information echo "" usage2 exit 0 elif [ $# -gt 9 ] 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) # get graphmode shift # to get the next parameter # test if parameter starts with minus sign errorMsg="--- INVALID GRAPHMODE SPECIFICATION ---" checkMinus "$1" case "$1" in curve) graphmode="curve";; C) graphmode="curve";; c) graphmode="curve";; points) graphmode="points";; P) graphmode="points";; p) graphmode="points";; *) errMsg="--- UNKNOWN GRAPHMODE ---" esac ;; -c) # get channel shift # to get the next parameter # test if parameter starts with minus sign errorMsg="--- INVALID CHANNEL SPECIFICATION ---" checkMinus "$1" channel=`echo "$1" | tr "[:upper:]" "[:lower:]"` case "$channel" in red) ;; green) ;; blue) ;; lightness) ;; brightness) ;; luma) ;; luminosity) ;; *) errMsg="--- UNKNOWN CHANNEL ---" esac ;; -f) # text file with point pairs opt=-f shift # to get the next parameter - point_file # test if parameter starts with minus sign errorMsg="--- INCORRECT POINT_FILE SPECIFICATION ---" checkMinus "$1" point_file=$1 #test if point_file is a valid file [ -f $point_file -a -r $point_file -a -s $point_file ] || errMsg "--- POINT FILE $point_file DOES NOT EXIST OR IS NOT AN ORDINARY FILE, NOT READABLE OR HAS ZERO SIZE ---" ;; -s) # scaling parameter shift # to get the next parameter # test if parameter starts with minus sign errorMsg="--- INCORRECT XSCALE,YSCALE SPECIFICATION ---" checkMinus "$1" # separate xscale and yscale and test for validity test=`expr "$1" : '^[0-9][0-9]*,[0-9][0-9]*$'` [ $test -eq 0 ] && errMsg "--- XSCALE AND/OR YSCALE ARE NOT INTEGERS ---" xscale=`echo "$1" | cut -d, -f1` yscale=`echo "$1" | cut -d, -f2` ;; -) # STDIN and end of arguments break ;; -*) # any other - argument errMsg "--- UNKNOWN OPTION ---" ;; *) # end of arguments break ;; esac shift # next option done fi # extract and test point pair values if [ "$opt" = "-f" ] then # get infile and outfile as the last arguments left infile=$1 outfile=$2 # put the file with line breaks into parm parms=`cat $point_file` # strip the line breaks (works ONLY if $parm is NOT put into quotes "$parm") parm=`echo $parms | grep '.*'` # first pattern below replaces all occurrences of commas and spaces with a space => 1 2 3 4 5 6 # second pattern below replaces the first occurrence of a space with a comma => 1,2[ 3 4][ 5 6] - ignore [], they are for emphasis only # third pattern below looks for all space number space number pairs and replaces them with a space followed by number1,number2 => 1,2 3,4 5,6 set - `echo "$parms" | sed 's/[, ][, ]*/ /g; s/ /,/; s/ \([^ ]*\) \([^ ]*\)/ \1,\2/g'` # test for valid positive floats for x and y # keep all points from file index=0 plist="" while [ $# -gt 0 ] do testFloatPair $1 plist="$plist $1" shift index=`expr $index + 1` done #remove leading space plist=`echo "$plist" | sed -n 's/ [ ]*\(.*\)/\1/p'` [ "$plist" = "" ] && errMsg "--- NO POINT PAIRS WERE PROVIDED ---" else # get plist, infile and outfile parms="$1" infile="$2" outfile="$3" # first pattern below replaces all occurrences of commas and spaces with a space => 1 2 3 4 5 6 # second pattern below replaces the first occurrence of a space with a comma => 1,2[ 3 4][ 5 6] - ignore [], they are for emphasis only # third pattern below looks for all space number space number pairs and replaces them with a space followed by number1,number2 => 1,2 3,4 5,6 set - `echo "$parms" | sed 's/[, ][, ]*/ /g; s/ /,/; s/ \([^ ]*\) \([^ ]*\)/ \1,\2/g'` # test for valid positive floats for x and y index=0 plist="" while [ $# -gt 0 ] do testFloatPair $1 plist="$plist $1" shift index=`expr $index + 1` done #remove leading space from plist plist=`echo "$plist" | sed -n 's/ [ ]*\(.*\)/\1/p'` [ "$plist" = "" ] && errMsg "--- NO POINT PAIRS WERE PROVIDED ---" fi # setup temporary images and auto delete upon exit # use mpc/cache to hold input image temporarily in memory tmpA="$dir/curves_$$.mpc" tmpB="$dir/curves_$$.cache" tmp1="$dir/curves_1_$$.png" # get outfile name before suffix outname=`echo "$outfile" | sed -n 's/^\([^.]*\)[.][^.]*$/\1/ p'` gg="_graph" tmp1="$dir/$outname$gg.gif" # remove temporaries if [ "$graph" = "view" ] then trap "rm -f $tmpA $tmpB $tmp1;" 0 trap "rm -f $tmpA $tmpB $tmp1; exit 1" 1 2 3 15 # trap "rm -f $tmpA $tmpB $tmp1; exit 1" ERR elif [ "$graph" = "save" ] then trap "rm -f $tmpA $tmpB;" 0 trap "rm -f $tmpA $tmpB; exit 1" 1 2 3 15 # trap "rm -f $tmpA $tmpB; exit 1" ERR else errMsg "--- NOT A VALID GRAPH DISPLAY OPTION ---" fi # test that infile provided [ "$infile" = "" ] && errMsg "--- NO INPUT FILE SPECIFIED ---" # test that outfile provided [ "$outfile" = "" ] && errMsg "--- NO OUTPUT FILE SPECIFIED ---" # test that last point pair not used instead of infile test=`expr "$infile" : '^[0-9]*,.*$'` [ $test -gt 0 ] && errMsg "--- INPUT/OUTPUT FILES IMPROPERLY SPECIFIED ---" # test input image if convert -quiet "$infile" +repage "$tmpA" then : 'do nothing special' else errMsg "--- FILE $infile DOES NOT EXIST OR IS NOT AN ORDINARY FILE, NOT READABLE OR HAS ZERO SIZE ---" fi # cubic spline interpolate using parametric format # x=a0+a1*s+a2*s^2+a3*s^3 # y=b0+b1*s+b2*s^2+b3*s^3 # Q=C¥S; where Q=(x;y)=polynomial coordinate (column) vector # and C=(a3 a2 a1 a0; b3 b2 b1 b0)=coefficient matrix with a's and b's as rows; # and S=(s^3 s^2 s 1)=parametric (row) vector # spline formulation often represented as: Q=S¥M¥V # where M=matrix which depends upon the type of spline # and V is the control (column) vector (often either a set of knots or derivatives; knots being data points) # x=(s^3 s^2 s 1)¥M¥Vx where Vx is (column) vector of four components (knots, tangents or contol point) # y=(s^3 s^2 s 1)¥M¥Vx where Vx is (column) vector of four components (knots, tangents or control points) # (alternate form is P=Vt¥Mt*Vt; Vt=V transposed so is a row vector; Mt=M transposed) # see references: # http://icie.cs.byu.edu/UIBook/12-2DGeometry.pdf # http://www.cs.cornell.edu/Courses/cs465/2004fa/lectures/15splines/15splines.pdf # http://evasion.inrialpes.fr/Membres/Francois.Faure/enseignement/M2R-Animation/interpolation.pdf # http://www.csie.ntu.edu.tw/~cyy/amt/lec03.ppt # http://www.cg.tuwien.ac.at/courses/Animation/c.ps # http://cubic.org/docs/hermite.htm # http://local.wasp.uwa.edu.au/~pbourke/other/interpolation/ # http://wiki.tcl.tk/10530 # catmull-rom vector of knots and matrix # V=(K0 K1 K2 K3); and interpolate between K1 and K2 # -1 3 -3 1 # 2 -5 4 -1 # -1 0 1 0 # 0 2 0 0 # start processing echo "" echo "Please Wait" echo "" # augment plist to add 0,0 and/or xscale,yscale if plist does not span 0 to xscale count=`echo "$plist" | wc -w` if [ $count -eq 1 ]; then firstx=`echo "$plist" | sed -n 's/^\([.0-9]*\),.*$/\1/p'` lastx=$firstx lasty=`echo "$plist" | sed -n 's/^.*,\([.0-9]*\)$/\1/p'` elif [ $count -gt 1 ]; then firstx=`echo "$plist" | sed -n 's/^\([.0-9]*\),.*$/\1/p'` lastx=`echo "$plist" | sed -n 's/^.* \([.0-9]*\),[.0-9]*$/\1/p'` lasty=`echo "$plist" | sed -n 's/^.*,\([.0-9]*\)$/\1/p'` else errMsg="--- INCORRECT NUMBER OF POINT PAIRS SUPPLIED ---" fi [ `echo "$firstx != 0" | bc` -eq 1 ] && plist="0,0 $plist" [ `echo "$lastx != $xscale" | bc` -eq 1 ] && plist="$plist $xscale,$yscale" # convert plist into pairArray for processing of spline pairArray=($plist) np=${#pairArray[*]} npm1=`expr $np - 1` npm2=`expr $np - 2` # separate x and y components of pairArray i=0 while [ $i -lt $np ]; do xArray[$i]=`echo "${pairArray[$i]}" | cut -d, -f1` yArray[$i]=`echo "${pairArray[$i]}" | cut -d, -f2` i=`expr $i + 1` done # augment pairArray with linearly extended first and last point pleftx=`echo "scale=6; 2*${xArray[0]}-${xArray[1]}/1" | bc` plefty=`echo "scale=6; 2*${yArray[0]}-${yArray[1]}/1" | bc` prightx=`echo "scale=6; 2*${xArray[$npm1]}-${xArray[$npm2]}/1" | bc` prighty=`echo "scale=6; 2*${yArray[$npm1]}-${yArray[$npm2]}/1" | bc` newplist="$pleftx,$plefty $plist $prightx,$prighty" pairArray=($newplist) np=${#pairArray[*]} npm1=`expr $np - 1` # function to apply catmull-rom basis matrix to knots catrom() { a3=`convert xc: -format "%[fx:0.5*(-($x0)+3*$x1-(3*$x2)+$x3)]" info:` a2=`convert xc: -format "%[fx:0.5*(2*$x0-(5*$x1)+4*$x2-($x3))]" info:` a1=`convert xc: -format "%[fx:0.5*(-($x0)+$x2)]" info:` a0=$x1 b3=`convert xc: -format "%[fx:0.5*(-$y0+3*$y1-(3*$y2)+$y3)]" info:` b2=`convert xc: -format "%[fx:0.5*(2*$y0-(5*$y1)+4*$y2-($y3))]" info:` b1=`convert xc: -format "%[fx:0.5*(-($y0)+$y2)]" info:` b0=$y1 #echo >&2 "ab=$a0, $a1, $a2, $a3, $b0, $b1, $b2, $b3" } # function to spline interpolate between two x,y pairs spline_interp() { pair0="$1" pair1="$2" pair2="$3" pair3="$4" x0=`echo "$pair0" | cut -d, -f1` y0=`echo "$pair0" | cut -d, -f2` x1=`echo "$pair1" | cut -d, -f1` y1=`echo "$pair1" | cut -d, -f2` x2=`echo "$pair2" | cut -d, -f1` y2=`echo "$pair2" | cut -d, -f2` x3=`echo "$pair3" | cut -d, -f1` y3=`echo "$pair3" | cut -d, -f2` #echo "xy=$x0,$y0 $x1,$y1 $x2,$y2 $x3,$y3" catrom #echo >&2 "ab=$a0, $a1, $a2, $a3, $b0, $b1, $b2, $b3" # range is horizontal distance in pixels between knots range=`convert xc: -format "%[fx:($x2-$x1)]" info:` numinc=`convert xc: -format "%[fx:floor($range/$pinc)]" info:` pinc=`convert xc: -format "%[fx:$range/$numinc]" info:` s=0 #echo "range=$range; numinc=$numinc; pinc=$pinc; $prightx" # do not include last value if this is not the last sequence as overlaps with first value in next sequence if [ "$x3" != "$prightx" ]; then op="<" else op="<=" fi points1=`AWK -v range="$range" -v numinc="$numinc" -v pinc="$pinc" -v op="$op" -v a0="$a0" \ -v a1="$a1" -v a2="$a2" -v a3="$a3" -v b0="$b0" -v b1="$b1" -v b2="$b2" -v b3="$b3" \ 'BEGIN { if ( op=="<=" ) { for (s=0; s <= numinc; s++) \ { s1=(s*pinc/range); s2=(s1*s1); s3=(s2*s1); print (a3*s3+a2*s2+a1*s1+a0), (b3*s3+b2*s2+b1*s1+b0); }; } \ else { for (s=0; s < numinc; s++) \ { s1=(s*pinc/range); s2=(s1*s1); s3=(s2*s1); print (a3*s3+a2*s2+a1*s1+a0), (b3*s3+b2*s2+b1*s1+b0); }; } }' |\ while read x y; do echo "$x,$y" done` # insert line break before each new section points="$points $points1" } # process pairArray to create spline points="" j=0 k=1 l=2 m=3 while [ $m -le $npm1 ]; do echo "Processing Segment $k" spline_interp ${pairArray[$j]} ${pairArray[$k]} ${pairArray[$l]} ${pairArray[$m]} #echo >&2 "ab=$a0, $a1, $a2, $a3, $b0, $b1, $b2, $b3" j=$k k=$l l=$m m=`expr $m + 1` done #edit control points to add leading 0, due to bug prior to IM 6.4.2-10 points=`echo "$points" | sed 's/[ ][ ]*\./ 0./g'` points=`echo "$points" | sed 's/,\./,0./g'` points=`echo "$points" | sed 's/-\./-0./g'` #remove leading spaces points=`echo "$points" | sed -n 's/^[ ]*\(.*\)$/\1/p'` # augment points so that form closed polygon for creating lut # note duplicate points do not matter plistnew="0,0 $points $xscale,$yscale $xscale,0" # ************* #echo "plistnew=$plistnew" # ************* # create and apply lut # trap for IM version config=`convert -list configure` 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` if [ "$im_version" -ge "06030507" ] then proc="-clut" else proc="-fx 'v.p{u*v.w,0}'" fi if [ "$im_version" -lt "06070607" ]; then cspace="RGB" else cspace="sRGB" fi # note results for below will be a bit too bright; alternative if leave off is way too dark if [ "$im_version" -ge "06070708" -a "$im_version" -le "06080504" ]; then setcspace="-set colorspace RGB" else setcspace="" fi if [ "$channel" = "red" ]; then cproc1="-channel red" cproc2="+channel" elif [ "$channel" = "green" ]; then cproc1="-channel green" cproc2="+channel" elif [ "$channel" = "blue" ]; then cproc1="-channel blue" cproc2="+channel" elif [ "$channel" = "lightness" ]; then cproc1="$setcspace -colorspace HSL -channel blue" cproc2="+channel -colorspace $cspace" elif [ "$channel" = "brightness" ]; then cproc1="$setcspace -colorspace HSB -channel blue" cproc2="+channel -colorspace $cspace" elif [ "$channel" = "luma" ]; then cproc1="$setcspace -colorspace YCbCr -channel red" cproc2="+channel -colorspace $cspace" elif [ "$channel" = "luminosity" ]; then cproc1="$setcspace -colorspace Lab -channel red" cproc2="+channel -colorspace $cspace" else cproc1="" cproc2="" fi # draw white polygon on black background # remove first row corresponding to zero as cannot have any white on this row. # then box average the columns to get the lut and apply it to the image. ww=`convert xc: -format "%[fx:$xscale+1]" info:` hh=`convert xc: -format "%[fx:$yscale+1]" info:` convert $tmpA \ \( -size ${ww}x${hh} xc:black -fill white \ -draw "polygon $plistnew" -alpha off \ -crop ${ww}x${yscale}+0+1 +repage \ -scale ${ww}x1! \) \ $cproc1 $proc $cproc2 "$outfile" # display graph if option -g if [ "$graphmode" != "" ] then echo "" echo "Break Points = $plist" echo "" echo "Curve Points = $points" echo "" convert -size 150x150 xc:white -stroke black -draw "rectangle 40,10 141,112" $tmp1 if [ "$graphmode" = "curve" ]; then convert $tmp1 \( -size 100x101 xc:white \ -draw "fill none stroke red polyline $points" -flip \) \ -compose over -geometry 100x101+41+11 -composite $tmp1 elif [ "$graphmode" = "points" ]; then pArray=($plist) num=${#pArray[*]} circles=$(for point in $plist; do x=`echo "$point" | cut -d, -f1` y=`echo "$point" | cut -d, -f2` xx=`convert xc: -format '%[fx:'"$x"'+'"$crad"']' info:` echo "circle $x,$y $xx,$y" done) convert $tmp1 \( -size 100x101 xc:white \ -draw "fill none stroke red polyline $points" \ -draw "fill blue stroke blue $circles" -flip \) \ -compose over -geometry 100x101+41+11 -composite $tmp1 fi convert $tmp1 -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'" $tmp1 convert -respect-parenthesis $tmp1 \( -background white -fill black -font Arial \ -pointsize 10 -gravity center label:'o \nu \nt \np \nu \nt ' -trim \) \ -geometry +10+20 -compose over -composite $tmp1 display $tmp1 fi exit 0