#!/bin/bash # # Developed by Fred Weinhaus 3/24/2014 .......... revised 3/1/2024 # # ------------------------------------------------------------------------------ # # 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: zerocrossing [-e edge ] [-l laplace] [-a amplifiy] [-s size] [-g] infile outfile # USAGE: zerocrossing [-h or -help] # # OPTIONS: # # -e edge edge type; choices are sobel (s) or morphologic (m); # default=sobel # -l laplace laplacian type; choices are: 0, 2 and 5; default=0 # -a amplify zero crossing percent amplification; integer>=0; # default=100 (no amplification) # -s size 2x morphologic disk size; values are integer>=2; # default=4 (values will be divided by 2 later) # -g convert image to grayscale before getting edges # -c contrast increase contrast of output (percent); integer>=0; # default=0 (no change) # ### # # NAME: ZEROCROSSING # # PURPOSE: To apply a zero crossing edge detector to image. # # DESCRIPTION: ZEROCROSSING applies a zero crossing edge detector to image # in order to thin the edges. The user may select either sobel or morphologic # for the basic type of edge detection as well as the type of laplacian used # for detecting the zero crossings. # # OPTIONS: # # -e edge ... EDGE type. The choices are sobel (s) or morphologic (m). The # default=sobel. # # -l laplace ... LAPLACIAN type. The choices are: 0, 2 and 5. The default=0. # # -a amplify ... AMPLIFICATION is the zero crossing percent amplification. # Values are integer>=0. The default=100 (no amplification). # # -s size ... SIZE is twice the morphologic disk size. Values are integer>=2. # The default=4 (values will be divided by 2 later). # # -g ... converts the input image to GRAYSCALE before extracting edges. # # -c ... CONTRAST increases the contrast of the output image (in percent). # Values are integers>=0. The default=0 (no change) # # REQUIREMENTS: IM 6.5.9.3 is required for the use of -morphology edges. IM # 6.6.1.8 is required for the use of sobel edges. # # 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 edge="sobel" # sobel, morphologic laplace="0" # laplacian type: 0,2,5 amplify=100 # zerocrossing amplification size=4 # morphology 2x disk size: integer>=2; default=4 grayscale="no" # convert to grayscale contrast=0 # contrast of output # 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 13 ] 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 ;; -e) # get edge shift # to get the next parameter # test if parameter starts with minus sign errorMsg="--- INVALID EDGE SPECIFICATION ---" checkMinus "$1" edge=`echo "$1" | tr '[A-Z]' '[a-z]'` case "$edge" in sobel|s) edge="sobel" ;; morphologic|m) edge="morphologic" ;; *) errMsg "--- EDGE=$edge IS AN INVALID VALUE ---" ;; esac ;; -l) # get laplace shift # to get the next parameter # test if parameter starts with minus sign errorMsg="--- INVALID LAPLACE SPECIFICATION ---" checkMinus "$1" laplace=`expr "$1" : '\([025]\)'` [ "$laplace" = "" ] && errMsg "--- LAPLACE=$laplace MUST BE EITHER 0, 2 OR 5 ---" ;; -a) # get amplify shift # to get the next parameter # test if parameter starts with minus sign errorMsg="--- INVALID AMPLIFY SPECIFICATION ---" checkMinus "$1" amplify=`expr "$1" : '\([0-9]*\)'` [ "$amplify" = "" ] && errMsg "--- AMPLIFY=$amplify MUST BE AN INTEGER ---" ;; -s) # get size shift # to get the next parameter # test if parameter starts with minus sign errorMsg="--- INVALID SIZE SPECIFICATION ---" checkMinus "$1" size=`expr "$1" : '\([0-9]*\)'` [ "$size" = "" ] && errMsg "SIZE=$size MUST BE A NON-NEGATIVE INTEGER ---" test1=`echo "$size < 2" | bc` [ $test1 -eq 1 ] && errMsg "--- SIZE=$size MUST BE AN INTEGER GREATER THAN 1 ---" ;; -g) # set grayscale grayscale="yes" ;; -c) # get contrast shift # to get the next parameter # test if parameter starts with minus sign errorMsg="--- INVALID CONTRAST SPECIFICATION ---" checkMinus "$1" contrast=`expr "$1" : '\([0-9]*\)'` [ "$contrast" = "" ] && errMsg "--- CONTRAST=$contrast MUST BE A NON-NEGATIVE INTEGER ---" ;; -) # 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 # setup temporary images tmpA1="$dir/zerocrossing_1_$$.mpc" tmpB1="$dir/zerocrossing_1_$$.cache" trap "rm -f $tmpA1 $tmpB1;" 0 trap "rm -f $tmpA1 $tmpB1; exit 1" 1 2 3 15 #trap "rm -f $tmpA1 $tmpB1; exit 1" ERR # read the input image into the temporary cached image and test if valid convert -quiet "$infile" +repage -alpha off "$tmpA1" || errMsg "--- FILE $infile DOES NOT EXIST OR IS NOT AN ORDINARY FILE, NOT READABLE OR HAS ZERO size ---" # 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 up grayscaling if [ "$grayscale" = "yes" ]; then gproc="-colorspace gray" else gproc="" fi # set up size --- divide by 2 size=`convert xc: -format "%[fx:$size/2]" info:` # setup edge processing if [ "$edge" = "sobel" ]; then eproc="-define convolve:scale=100% -define morphology:compose=Lighten -morphology Convolve Sobel:'>'" elif [ "$edge" = "morphologic" ]; then eproc="-morphology edge disk:$size -auto-level " fi # set up for biasing if [ "$im_version" -ge "07000000" ]; then biasing="-define convolve:bias=50%" else biasing="-bias 50%" fi # create zero crossing # line1: convert to grayscale if desired # line2: create sobel or morphologic edges # line3: create laplacian # lines4-7: apply gradient magnitude to laplacian to get zero crossings # note: cannot just threshold laplacian at mid gray, since background flat areas are also gray # line 8: delete tmps and multiply zero crossing laplacian by edge (sobel or morphologic) image convert $tmpA1 $gproc \ \( -clone 0 $eproc \) \ \( -clone 0 $biasing -morphology Convolve Laplacian:$laplace -clamp \) \ \( -clone 2 -define convolve:scale="$amplify%" -morphology convolve sobel:0 -clamp -evaluate pow 2 \) \ \( -clone 2 -define convolve:scale="$amplify%" -morphology convolve sobel:90 -clamp -evaluate pow 2 \) \ -delete 0,2 \ \( -clone 1 -clone 2 -compose plus -composite -evaluate pow 0.5 -negate -threshold 0 -negate \) \ -delete 1,2 -compose multiply -composite \ -contrast-stretch 0x$contrast% \ "$outfile" exit 0