#!/bin/bash # # Developed by Fred Weinhaus 9/20/2007 .......... 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: laplacian [-f filter] [t thresh] [-m mix] infile outfile # USAGE: laplacian [-h or -help] # # OPTIONS: # # -f filter filter=1 to 5 (in order of increasing # edge strength); default=1 # -t thresh threshold percent for binarization; # thresh=integer 0 to 100; default="" (none) # -m mix mixing percent with original image; # mix=integer 0 to 100; default=100 # -h get help information # -help get help information # ### # # NAME: LAPLACIAN # # PURPOSE: To apply a Laplacian filter to an image. # # DESCRIPTION: LAPLACIAN generates an output image which is a user defined mix # or blend of the original image and a Laplacian convolution filtered version # of the image. This is achieved by forming a single convolution kernel whose # weights depend upon a mixing of the Laplacian coefficients and the identity # kernel. The script applies one of three different 3x3 Laplacian filters to # an image to extract or enhance the edges in the image. It is a type of high # pass filter which is constructed from the sum of the x and y second derivatives. # # The basic blended high pass filtering formula is F = (1-m)*I + m*L, where I # is the original image, L is the Laplacian high pass filtered image and m = # mix/100. When m=0, we get only the original image and when m=1, we get only # the high pass Laplacian filtered image. For intermediate value of m, we # get a blend of the image and the Laplacian high pass filtered image. Now, # we can consider both I and L as a convolution of some kernel with the # original image, namely I = i x I and L = l x I, where x means convolution. # Note that a convolution is simply a weighted average of all the pixels in # some neighborhood of a give pixel. Usually an odd sized neighborhood, such # as 3x3, etc is used to prevent having the resulting image be shifted a # fractional pixel. The convolution kernel values are simply the weights for # the average. So here, i is the identity kernel, which is all zeroes, except # the center of the kernel which has a value of 1. Similarly, l is one of the # three Laplacian kernels. They are different forms of a high pass filter. # Thus we can consider the final filtered image, F = f x I, where f = (1-m)*i # + m*l. Consequently, we only have to do one convolution using the # convolution kernel, f. Note, that all pure high pass filter convolution # kernels will have weights that sum to 0. Also note, that the filters are # actually the negatives of the true laplacian filters so that when mixed # with the image they produce sharpening rather than blurring. For example, # applying Laplacian 3 is equivalent the identity kernel minus the 3x3 average # convolution kernel. # # OPTIONS: # # -f filter is the form of the filter. Three different 3x3 filters, one 5x5 # filter and one 7x7 filters are provided in order of the increasing edge # strength they produce. Values for filter are 1 to 5. The default is filter=1. # # Laplacian 1 # 0 -1 0 # -1 4 -1 # 0 -1 0 # # Laplacian 2 # -2 1 -2 # 1 4 1 # -2 1 -2 # # Laplacian 3 # -1 -1 -1 # -1 8 -1 # -1 -1 -1 # # Laplacian 4 # -4 -1 0 -1 -4 # -1 2 3 2 -1 # 0 3 4 3 0 # -1 2 3 2 -1 # -4 -1 0 -1 -4 # # Laplacian 5 # -10 -5 -2 -1 -2 -5 -10 # -5 0 3 4 3 0 -5 # -2 3 6 7 6 3 -2 # -1 4 7 8 7 4 -1 # -2 3 6 7 6 3 -2 # -5 0 3 4 3 0 -5 # -10 -5 -2 -1 -2 -5 -10 # # -t thresh is the thresholding percentage used to create a binary Laplacian # edge image. Values range from 0 to 100. A higher value will result in # fewer edges in the resulting image. # # -m mix is the percentage mixing factor used to blend the Laplacian with # the original image. A value of mix=0, results in the original image. A # value of mix=100 results in a pure Laplacian filtered image. # # 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 params filter=1 mix=100 thresh="" # set directory for temporary files dir="." # suggestions are dir="." or dir="/tmp" # define Laplacian filters # Laplacian 1 (4-neighbor) # 0 -1 0 # -1 4 -1 # 0 -1 0 L1="0,-1,0,-1,4,-1,0,-1,0" # Laplacian 2 (d2x + d2y) # -2 1 -2 # 1 4 1 # -2 1 -2 L2="-2,1,-2,1,4,1,-2,1,-2" # Laplacian 3 (8-neighbor) # -1 -1 -1 # -1 8 -1 # -1 -1 -1 L3="-1,-1,-1,-1,8,-1,-1,-1,-1" # Laplacian 4 (d2x + d2y) # -4 -1 0 -1 -4 # -1 2 3 2 -1 # 0 3 4 3 0 # -1 2 3 2 -1 # -4 -1 0 -1 -4 L4="-4,-1,0,-1,-4,-1,2,3,2,-1,0,3,4,3,0,-1,2,3,2,-1,-4,-1,0,-1,-4" # Laplacian 5 (d2x + d2y) # -10 -5 -2 -1 -2 -5 -10 # -5 0 3 4 3 0 -5 # -2 3 6 7 6 3 -2 # -1 4 7 8 7 4 -1 # -2 3 6 7 6 3 -2 # -5 0 3 4 3 0 -5 # -10 -5 -2 -1 -2 -5 -10 L5="-10,-5,-2,-1,-2,-5,-10,-5,0,3,4,3,0,-5,-2,3,6,7,6,3,-2,-1,4,7,8,7,4,-1,-2,3,6,7,6,3,-2,-5,0,3,4,3,0,-5,-10,-5,-2,-1,-2,-5,-10" # 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 [ $# -eq 3 -o $# -eq 5 -o $# -eq 7 -o $# -gt 8 ] 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 filter shift # to get the next parameter - filter # test if parameter starts with minus sign errorMsg="--- INVALID LAPLACIAN FILTER SPECIFIED ---" checkMinus "$1" filter="$1" # test filter values [ $filter -lt 1 -o $filter -gt 5 ] && errMsg "--- FILTER=$filter IS NOT A VALID VALUE ---" ;; -t) # get thresh shift # to get the next parameter - thresh # test if parameter starts with minus sign errorMsg="--- INVALID THRESHOLD SPECIFICATION ---" checkMinus "$1" # test thresh values thresh=`expr "$1" : '\([0-9]*\)'` [ "$thresh" = "" ] && errMsg "--- THRESH=$thresh MUST BE AN INTEGER ---" threshtestA=`echo "$mix < 0" | bc` threshtestB=`echo "$mix > 100" | bc` [ $threshtestA -eq 1 -o $threshtestB -eq 1 ] && errMsg "--- THRESH=$thresh MUST BE AN INTEGER BETWEEN 0 AND 100 ---" ;; -m) # get mix shift # to get the next parameter - mix # test if parameter starts with minus sign errorMsg="--- INVALID MIX SPECIFICATION ---" checkMinus "$1" # test mix values mix=`expr "$1" : '\([0-9]*\)'` [ "$mix" = "" ] && errMsg "--- MIX=$mix MUST BE AN INTEGER ---" mixtestA=`echo "$mix < 0" | bc` mixtestB=`echo "$mix > 100" | bc` [ $mixtestA -eq 1 -o $mixtestB -eq 1 ] && errMsg "--- MIX=$mix MUST BE AN INTEGER BETWEEN 0 AND 100 ---" ;; -) # 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 ---" # test if image an ordinary, readable and non-zero size if [ -f $infile -a -r $infile -a -s $infile ] then : 'do nothing - proceed' else errMsg "--- FILE $infile DOES NOT EXIST OR IS NOT AN ORDINARY FILE, NOT READABLE OR HAS ZERO SIZE ---" exit 1 fi # setup temporary images and auto delete upon exit tmp0="$dir/laplacian_0_$$.miff" trap "rm -f $tmp0;" 0 trap "rm -f $tmp0; exit 1" 1 2 3 15 trap "rm -f $tmp0; 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` # specify filter # get filter [ $filter -eq 1 ] && lap=$L1 [ $filter -eq 2 ] && lap=$L2 [ $filter -eq 3 ] && lap=$L3 [ $filter -eq 4 ] && lap=$L4 [ $filter -eq 5 ] && lap=$L5 # convert 1D laplacian to array for later use kern=`echo $lap | sed 's/,/ /g'` kernArr=($kern) num=${#kernArr[*]} width=`echo "scale=0; sqrt($num)" | bc -l` # print 2D laplacian k=0 for ((i=0; i