#!/bin/bash # # Developed by Fred Weinhaus 7/30/2008 .......... revised 12/9/2023 # # ------------------------------------------------------------------------------ # # 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: polar [-m mode] [-c xc,yc] [-r rmn,rmx] [-a amn,amx] [-v vpmode] [-b bgcolor] infile outfile # USAGE: polar [-h or -help] # # OPTIONS: # # -m mode rect2polar or polar2rect; default=rect2polar # -c xc,yc coordinates of the transformation center; # default is image center # -r rmn,rmx min and max radius; default=0,(half image diagonal); # non-negative floats; rmx can be w, h, d or m for # width/2, height/2, diagonal/2 or min(width,height)/2 of image # -a amn,amx min and max angle; default=-180,180; # floats between -180 and 180 # -v vpmode virtual-pixel mode to use to fill area of output image # that are outside the input image; default=edge # -b bgcolor background color for virtual-pixel=background # any valid IM color is allowed. The default=black # ### # # NAME: POLAR # # PURPOSE: To apply either a rectangular (Cartesian) to polar transformation # or a polar to rectangular (Cartesian) transformation on an image. # # DESCRIPTION: POLAR applies either a rectangular (Cartesian) to polar transformation # or a polar to rectangular (Cartesian) transformation on an image. The user # has control of the range of radius, angle and center in the transformation. # # # ARGUMENTS: # # -m mode ... MODE is the transformation mode, which can be either rect2polar # (rectangular to polar) or polar2rect (polar to rectangular). The former, rect2polar, # treats the input as a normal rectangular image with columns representing X # and rows representing Y and treats the output as having columns representing angle # and rows representing radius. The latter, polar2rect, treats the input as having # columns representing angle and rows representing radius and treats the output as # having columns representing X and rows representing Y. Note that in a polar image, # nominally the left column is angle=amn=-180, the middle column is angle=0 and the # right column is angle=amx=180. Similarly, the top row is radius=rmn=0 and the # bottom row is radius=rmx=(half image diagonal). # # -c xc,yc ... XC,YC are the pixel coordinates for the transformation center. # The default is the image center. # # -r rmn,rmx ... RMN,RMX are the min and max radii. By default, rmn=0 and # rmx=(half image diagonal). This provides a transformation that includes # the whole image. However, for the rect2polar mode, this will cause the # output image to contain areas that are outside the input image. They will # be filled as determined by the virtual pixel setting. Values are non-negative # floats. Values are generally non-negative floats, but four other choices # are allowed: w, h, d and m, where w=width/2, h=height/2, d=diagonal/2 and # m=min(width,height)/2. # # -a amn,amx ... AMN,AMX are the min and max angles. By default, amn=-180 and # amx=180. Values for amn and amx are floats between -180 and 180. # # -v vpmode ... VPMODE is the virtual-pixel mode. Any valid IM virtual-pixel # setting is allowed. The default is edge. # # -b bgcolor ... BGCOLOR is the background color to use with vpmode=background. # Any valid IM color may be used. The default is black. # # Note that this script may be slow due to the use of -fx. # # 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 mode="rect2polar" xc="" yc="" rmn=0 rmx="d" amn=-180 amx=180 vpmode="edge" bgcolor="black" # 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 14 ] 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 ;; -m) # get mode shift # to get the next parameter # test if parameter starts with minus sign errorMsg="--- INVALID MODE SPECIFICATION ---" checkMinus "$1" mode="$1" [ "$mode" != "rect2polar" -a "$mode" != "polar2rect" ] && errMsg "--- INVALID MODE VALUE ---" ;; -c) # get coords shift # to get the next parameter # test if parameter starts with minus sign errorMsg="--- INVALID COORDS SPECIFICATION ---" checkMinus "$1" test=`echo "$1" | tr "," " " | wc -w` [ $test -eq 1 -o $test -gt 2 ] && errMsg "--- INCORRECT NUMBER OF COORDINATES SUPPLIED ---" coords=`expr "$1" : '\([.0-9]*,[.0-9]*\)'` [ "$coords" = "" ] && errMsg "--- COORDS=$coords MUST BE A PAIR OF NON-NEGATIVE FLOATS SEPARATED BY A COMMA ---" coords="$1," xc=`echo "$coords" | cut -d, -f1` yc=`echo "$coords" | cut -d, -f2` ;; -a) # get amn,amx angles shift # to get the next parameter # test if parameter starts with minus sign errorMsg="--- INVALID ANGLE SPECIFICATION ---" test=`echo "$1" | tr "," " " | wc -w` [ $test -eq 1 -o $test -gt 2 ] && errMsg "--- INCORRECT NUMBER OF ANGLES SUPPLIED ---" angles=`expr "$1" : '\([-.0-9]*,[-.0-9]*\)'` [ "$angles" = "" ] && errMsg "--- ANGLE=$angles MUST BE A NON-NEGATIVE FLOAT ---" amn=`echo "$angles" | cut -d, -f1` amx=`echo "$angles" | cut -d, -f2` amntestA=`echo "$amn < -180" | bc` amntestB=`echo "$amn > 180" | bc` [ $amntestA -eq 1 -o $amntestB -eq 1 ] && errMsg "--- AMN=$amn MUST BE A FLOAT BETWEEN -180 AND 180 ---" amxtestA=`echo "$amx < -180" | bc` amxtestB=`echo "$amx > 180" | bc` [ $amxtestA -eq 1 -o $amxtestB -eq 1 ] && errMsg "--- AMX=$amx MUST BE A FLOAT BETWEEN -180 AND 180 ---" test=`echo "$amn >= $amx" | bc` [ $test -eq 1 ] && errMsg "--- AMX=$amx MUST BE GREATER THAN AMN=$amn ---" ;; -r) # get rmn,rmx radii shift # to get the next parameter # test if parameter starts with minus sign errorMsg="--- INVALID RADIUS SPECIFICATION ---" checkMinus "$1" test=`echo "$1" | tr "," " " | wc -w` [ $test -eq 1 -o $test -gt 2 ] && errMsg "--- INCORRECT NUMBER OF RADII SUPPLIED ---" radii=`expr "$1" : '\([.0-9]*,[.0-9]*\)'` [ "$radii" = "" ] && radii=`expr "$1" : '\([.0-9]*,[whdm]\)'` [ "$radii" = "" ] && errMsg "--- RADII=$radii MUST BE A PAIR OF NON-NEGATIVE FLOATS SEPARATED BY A COMMA OR USE THE LETTERS W, H, D OR M ---" radii="$1," rmn=`echo "$radii" | cut -d, -f1` rmx=`echo "$radii" | cut -d, -f2` ;; -v) # get vpmode shift # to get the next parameter # test if parameter starts with minus sign errorMsg="--- INVALID VIRTUAL-PIXEL SPECIFICATION ---" checkMinus "$1" vpmode="$1" ;; -b) # get bgcolor shift # to get the next parameter # test if parameter starts with minus sign errorMsg="--- INVALID BACKGROUND COLOR SPECIFICATION ---" checkMinus "$1" bgcolor="$1" ;; -) # 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 [ "$outfile" = "" ] && errMsg "NO OUTPUT FILE SPECIFIED" tmpA="$dir/polar_$$.mpc" tmpB="$dir/polar_$$.cache" 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 # 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` if [ "$im_version" -ge "07000000" ]; then identifying="magick identify" else identifying="identify" fi if convert -quiet "$infile" +repage "$tmpA" then # set default values w2=`$identifying -format "%[fx:w/2]" $tmpA` h2=`$identifying -format "%[fx:h/2]" $tmpA` d2=`$identifying -format "%[fx:sqrt(w*w+h*h)/2]" $tmpA` m2=`$identifying -format "%[fx:min(w,h)/2]" $tmpA` centx=`$identifying -format "%[fx:(w-1)/2]" $tmpA` centy=`$identifying -format "%[fx:(h-1)/2]" $tmpA` [ "$rmx" = "w" ] && rmx=$w2 [ "$rmx" = "h" ] && rmx=$h2 [ "$rmx" = "d" ] && rmx=$d2 [ "$rmx" = "m" ] && rmx=$m2 [ "$xc" = "" ] && xc=$centx [ "$yc" = "" ] && yc=$centy fi #echo "mode=$mode: w=$w2; h=$h2; d=$d2; m=$m2; xc=$xc; yc=$yc; rmn=$rmn; rmx=$rmx; amn=$amn; amx=$amx" # rect to polar general equations (for inverse transformation) # note reverse of x and y as angle is measured from y axis not x axis # x=r*sin(angle) # y=r*cos(angle) # polar to rect general equations (for inverse transformation) # note reversal of order of x,y in arctan2 due to angle measured from y axis # r=sqrt(x^2 + y^2) # angle=arctan2(x,y) # 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` # set channel if bgcolor=none if [ "$bgcolor" = "none" ]; then channel="-channel rgba -alpha on" else channel="" fi # set up equations and do processing # rect2polar if [ "$mode" = "rect2polar" ]; then yy="yy=((j-$rmn)*$rmx/(h-1))*cos((($amx-($amn))*pi/180)*(i/(w-1))+($amn*pi/180))+$yc;" xx="xx=((j-$rmn)*$rmx/(h-1))*sin((($amx-($amn))*pi/180)*(i/(w-1))+($amn*pi/180))+$xc;" convert $infile -virtual-pixel $vpmode -background $bgcolor -monitor \ -fx "$xx $yy u.p{xx,yy}" +monitor "$outfile" fi # polar2rect if [ "$mode" = "polar2rect" ]; then if [ "$im_version" -ge "06030600" ]; then rr="rr=hypot((i-$xc),(j-$yc));" else rr="rr=sqrt((i-$xc)*(i-$xc) + (j-$yc)*(j-$yc));" fi aa="aa=atan2((i-$xc),(j-$yc));" xx="xx=(aa-(pi/180)*$amn)*(w-1)/((pi/180)*($amx-($amn)));" yy="yy=(rr-($rmn))*(h-1)/($rmx-($rmn));" convert $infile -virtual-pixel $vpmode -background $bgcolor -monitor \ -fx "$rr $aa $xx $yy u.p{xx,yy}" +monitor "$outfile" fi exit 0