#!/bin/bash # # Developed by Fred Weinhaus 7/8/2024 ..... revised 7/8/2024 # # ------------------------------------------------------------------------------ # # 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: unwatermark [-c close] [-d dilate] infile outfile # # USAGE: unwatermark [-h|-help] # # OPTIONS: # # -c close close morphology disk kernel size to extract watermark from # image; float>0; default=3 # -d dilate dilate morphology disk kernel size on watermark mask image; # float>0; default=1.5 # -s save save intermediate images: watermark (w), mask (m) or both (b) # as PNG format named after input. # ### # # NAME: UNWATERMARK # # PURPOSE: To remove a larger (uniform colored) watermark from a small font text image. # # DESCRIPTION: UNWATERMARK removes a larger (uniform colored) watermark from a # small font text image. # # OPTIONS: # # -c close ... CLOSE morphology disk kernel size to extract watermark from the image. # Values are floats>0. The default=3. The kernel diameter should be larger than the # smaller font text and much smaller than the larger uniform colored watermark # text. (diameter = 2*radius = 2*3*close (approx.); diameter for close=3 is 2*3*3=18) # # -d dilate ... DILATE morphology disk kernel size on watermark mask image. Values # are floats>=0. The default=1.5 # # -s save ... SAVE intermediate images; choices are: watermark (w), mask (m) or # both (b) as PNG format named after input. Default is no save images. # # REQUIREMENTS: Requires IM 7 in order to get the median color of just the watermark # in the image. # # REFERENCE: Christoph Rackwitz's Python Code at: # https://stackoverflow.com/questions/78130983/opencv-remove-watermark/78672690#78672690 # # 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 close=3 # close value dilate=1.5 # dilate value save=(none) # save intermediate images # set directory for temporary files tmpdir="." # suggestions are tmpdir="." or tmpdir="/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 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 ;; -c) # get close shift # to get the next parameter # test if parameter starts with minus sign errorMsg="--- INVALID CLOSE SPECIFICATION ---" #checkMinus "$1" close=`expr "$1" : '\([0-9.]*\)'` [ "$close" = "" ] && errMsg "--- CLOSE=$close MUST BE A NON-NEGATIVE FLOAT ---" test=`echo "$close == 0" | bc` [ $test -eq 1 ] && errMsg "--- CLOSE=$CLOSE MUST BE A POSITIVE FLOAT ---" ;; -d) # get dilate shift # to get the next parameter # test if parameter starts with minus sign errorMsg="--- INVALID DILATE SPECIFICATION ---" #checkMinus "$1" dilate=`expr "$1" : '\([0-9.]*\)'` [ "$dilate" = "" ] && errMsg "--- DILATE=$dilate MUST BE A NON-NEGATIVE FLOAT ---" ;; -s) # get save shift # to get the next parameter # test if parameter starts with minus sign errorMsg="--- INVALID SAVE SPECIFICATION ---" checkMinus "$1" save=`echo "$1" | tr '[A-Z]' '[a-z]'` case "$save" in watermark|w) save=watermark;; mask|m) save=mask;; both|b) save=both;; *) errMsg "--- SAVE=$save IS AN INVALID VALUE ---" esac ;; -) # 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 [ "$outfile" = "" ] && errMsg "NO OUTPUT FILE SPECIFIED" # define dir dir="$tmpdir/UNSATURATEHUE.$$" mkdir "$dir" || errMsg "--- FAILED TO CREATE TEMPORARY FILE DIRECTORY ---" trap "rm -rf $dir;" 0 trap "rm -rf $dir; exit 1" 1 2 3 15 trap "rm -rf $dir; exit 1" ERR 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` [ "$im_version" -lt "07000000" ] && errMsg "--- REQUIRES IM VERSION 7.0.0-0 OR HIGHER ---" # read input image convert -quiet "$infile" +repage $dir/tmpI.mpc || echo "--- FILE $infile DOES NOT EXIST OR IS NOT AN ORDINARY FILE, NOT READABLE OR HAS ZERO SIZE ---" # get inname inname=`convert -ping "$infile" -format "%t" info:` # set up for DILATE if [ "$dilate" = "0" ]; then dilating="" else dilating="-morphology dilate disk:$dilate" fi # do a close on image to remove small black text leaving just the watermark # process image as grayscale to get mask convert "$infile" \ -colorspace gray +write $dir/gray.miff \ -morphology close disk:4 +write $dir/watermark_gray.miff \ -auto-threshold otsu -negate \ $dilating $dir/mask.miff # get median color of watermark median_color=`convert "$infile" $dir/mask.miff -compose copy_opacity -composite \ -channel-fx "alpha=>read-mask" -channel rgb -alpha off \ -format "srgb(%[fx:255*median.r],%[fx:255*median.g],%[fx:255*median.b])\n" info:` echo "median_color=$median_color" # colorize the mask to form the colored watermark convert $dir/mask.miff \( +clone -fill "$median_color" -colorize 100 \) \ -colorspace sRGB -compose multiply -composite $dir/watermark.miff # get a correction factor from estimate of gray value from inverse of median correct_factor=`convert $dir/gray.miff $dir/mask.miff -compose copy_opacity -composite \ -channel-fx "alpha=>read-mask" -channel rgb -format "%[fx:1/median]\n" info:` echo "correct_factor=$correct_factor;" # correct grayscale image by multiplying by correction factor # then replace gray image with corrected gray where mask is white and input where mask is black # save result convert $dir/gray.miff -write mpr:gray \ -evaluate multiply $correct_factor +channel \ mpr:gray +swap $dir/mask.miff -compose over -composite \ $outfile # save intermediate images if [ "$save" = "watermark" -o "$save" = "both" ]; then convert $dir/watermark.miff "${inname}_watermark.png" fi if [ "$save" = "mask" -o "$save" = "both" ]; then convert $dir/mask.miff "${inname}_mask.png" fi exit 0