#!/bin/bash # # Developed by Fred Weinhaus 6/29/2008 .......... 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: captcha [-f font] [-p pointsize] [-t textcolor] [-u undercolor] [-b bordercolor] [-m mode] [-a angle] [-r resize] outfile # USAGE: captcha [-h or -help] # # OPTIONS: # # -f font fontname or path-to-font-file; default=TimesNewRoman # -p pointsize pointsize for font; default=40 # -t textcolor color of text; any IM color specification; default=black # -u undercolor background color under text; any IM color specification; # default=white; # -b bordercolor color of image border; any IM color specification; # default=black; # -m mode mode to orient text: skew, rotate, both; default=skew # -a angle maximum orientation angle of text used with mode; # default=40 (degrees). Values are integers 0<=angle<=60 # -r resize output image resize in percent; default=100 (percent) which # produces an image 300x80 pixels # ### # # NAME: CAPTCHA # # PURPOSE: To create a six-alphanumeric-character image for use as a challenge # response test. # # DESCRIPTION: CAPTCHA creates a six-alphanumeric-character image for use as a challenge # response test. It builds a default image of size 300x80 pixels containing 6 alphanumeric # characters that are randomly positioned and oriented and overlaid with random curved and # straight lines segments. # # # ARGUMENTS: # # -f font ... FONT is the desired font or path-to-font-file for the text. The default # is TimesNewRoman. # # -p pointsize ... POINTSIZE is the desired pointsize for the font. The default is 40. # # -t textcolor ... TEXTCOLOR is the color to apply to the text. Any valid IM # text color may be used. The default is black. # See http://imagemagick.org/script/color.php # # -u undercolor ... UNDERCOLOR is the background color to apply directly under the text. # Any valid IM text color may be used. The default is white. # See http://imagemagick.org/script/color.php # # -b bordercolor ... BORDERCOLOR is the color to apply to the image border. # Any valid IM text color may be used. The default is black. # See http://imagemagick.org/script/color.php # # -m mode ... MODE is the mode for randomly orienting the text. The choices are: # skew, rotate or both. # # -a angle ... ANGLE is the maximum angle to use to randomly orient the text. # The default=40 (degrees). # # -r resize ... RESIZE is the percentage of the default output image size of 300x80 # to use to generate the output image. The default is 100 (percent). All images are # created at a size of 300x80, including a 5 pixel border. If resize is specified, # the output image will be resized accordingly by a post-processing step using # the IM -resize function. # # NOTE: Some effects require the use of -fx and thus will be slower than the others. # These include: the variations on bulge, concave, convex and pinch. # # 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="skew" angle="40" font="TimesNewRoman" pointsize="40" textcolor="black" bordercolor="black" undercolor="white" resize=100 # 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 17 ] 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 font shift # to get the next parameter # test if parameter starts with minus sign errorMsg="--- INVALID FONT SPECIFICATION ---" checkMinus "$1" font="$1" ;; -p) # get pointsize shift # to get the next parameter # test if parameter starts with minus sign errorMsg="--- INVALID POINTSIZE SPECIFICATION ---" checkMinus "$1" pointsize=`expr "$1" : '\([0-9]*\)'` [ "$pointsize" = "" ] && errMsg "--- POINTSIZE=$pointsize MUST BE A NON-NEGATIVE INTEGER ---" pointsizetestA=`echo "$pointsize <= 0" | bc` [ $pointsizetestA -eq 1 ] && errMsg "--- POINTSIZE=$pointsize MUST BE AN INTEGER GREATER THAN 0 ---" ;; -t) # get textcolor shift # to get the next parameter # test if parameter starts with minus sign errorMsg="--- INVALID TEXTCOLOR SPECIFICATION ---" checkMinus "$1" textcolor="$1" ;; -u) # get undercolor shift # to get the next parameter # test if parameter starts with minus sign errorMsg="--- INVALID UNDERCOLOR SPECIFICATION ---" checkMinus "$1" undercolor="$1" ;; -b) # get bordercolor shift # to get the next parameter # test if parameter starts with minus sign errorMsg="--- INVALID BORDERCOLOR SPECIFICATION ---" checkMinus "$1" bordercolor="$1" ;; -m) # get mode shift # to get the next parameter # test if parameter starts with minus sign errorMsg="--- INVALID MODE SPECIFICATION ---" checkMinus "$1" mode="$1" #convert mode to lowercase mode=`echo "$mode" | tr "[:upper:]" "[:lower:]"` case "$mode" in skew) ;; rotate) ;; both) ;; *) errMsg "--- MODE=$mode IS AN INVALID VALUE ---" esac ;; -a) # get angle shift # to get the next parameter # test if parameter starts with minus sign errorMsg="--- INVALID ANGLE SPECIFICATION ---" checkMinus "$1" angle=`expr "$1" : '\([0-9]*\)'` [ "$angle" = "" ] && errMsg "--- angle=$angle MUST BE A NON-NEGATIVE INTEGER ---" angletestA=`echo "$angle < 0" | bc` angletestB=`echo "$angle > 60" | bc` [ $angletestA -eq 1 -o $angletestB -eq 1 ] && errMsg "--- angle=$angle MUST BE AN INTEGER BETWEEN 0 AND 60 ---" ;; -r) # get resize shift # to get the next parameter # test if parameter starts with minus sign errorMsg="--- INVALID RESIZE SPECIFICATION ---" checkMinus "$1" resize=`expr "$1" : '\([0-9]*\)'` [ "$resize" = "" ] && errMsg "--- RESIZE=$resize MUST BE A NON-NEGATIVE INTEGER ---" resizetestA=`echo "$resize <= 0" | bc` [ $resizetestA -eq 1 ] && errMsg "--- RESIZE=$resize MUST BE AN INTEGER GREATER THAN 0 ---" ;; -) # STDIN and end of arguments break ;; -*) # any other - argument errMsg "--- UNKNOWN OPTION ---" ;; *) # end of arguments break ;; esac shift # next option done # # get outfile outfile="$1" fi # test that outfile provided [ "$outfile" = "" ] && errMsg "NO OUTPUT FILE SPECIFIED" # set up temporary file tmp0="$dir/captcha_0_$$.miff" trap "rm -f $tmp0;" 0 trap "rm -f $tmp0; exit 1" 1 2 3 15 trap "rm -f $tmp0; exit 1" ERR # compute random positions and orientations and characters xx1=`convert xc: -format "%[fx: -120 + sign(rand()-0.5)*floor(5*rand()+0.5)]" info:` xx2=`convert xc: -format "%[fx: -72 + sign(rand()-0.5)*floor(5*rand()+0.5)]" info:` xx3=`convert xc: -format "%[fx: -24 + sign(rand()-0.5)*floor(5*rand()+0.5)]" info:` xx4=`convert xc: -format "%[fx: 24 + sign(rand()-0.5)*floor(5*rand()+0.5)]" info:` xx5=`convert xc: -format "%[fx: 72 + sign(rand()-0.5)*floor(5*rand()+0.5)]" info:` xx6=`convert xc: -format "%[fx: 120 + sign(rand()-0.5)*floor(5*rand()+0.5)]" info:` yy1=`convert xc: -format "%[fx: sign(rand()-0.5)*floor(10*rand()+0.5)]" info:` yy2=`convert xc: -format "%[fx: sign(rand()-0.5)*floor(10*rand()+0.5)]" info:` yy3=`convert xc: -format "%[fx: sign(rand()-0.5)*floor(10*rand()+0.5)]" info:` yy4=`convert xc: -format "%[fx: sign(rand()-0.5)*floor(10*rand()+0.5)]" info:` yy5=`convert xc: -format "%[fx: sign(rand()-0.5)*floor(10*rand()+0.5)]" info:` yy6=`convert xc: -format "%[fx: sign(rand()-0.5)*floor(10*rand()+0.5)]" info:` rr1=`convert xc: -format "%[fx: sign(rand()-0.5)*floor($angle*rand()+0.5)]" info:` rr2=`convert xc: -format "%[fx: sign(rand()-0.5)*floor($angle*rand()+0.5)]" info:` rr3=`convert xc: -format "%[fx: sign(rand()-0.5)*floor($angle*rand()+0.5)]" info:` rr4=`convert xc: -format "%[fx: sign(rand()-0.5)*floor($angle*rand()+0.5)]" info:` rr5=`convert xc: -format "%[fx: sign(rand()-0.5)*floor($angle*rand()+0.5)]" info:` rr6=`convert xc: -format "%[fx: sign(rand()-0.5)*floor($angle*rand()+0.5)]" info:` ss1=`convert xc: -format "%[fx: sign(rand()-0.5)*floor($angle*rand()+0.5)]" info:` ss2=`convert xc: -format "%[fx: sign(rand()-0.5)*floor($angle*rand()+0.5)]" info:` ss3=`convert xc: -format "%[fx: sign(rand()-0.5)*floor($angle*rand()+0.5)]" info:` ss4=`convert xc: -format "%[fx: sign(rand()-0.5)*floor($angle*rand()+0.5)]" info:` ss5=`convert xc: -format "%[fx: sign(rand()-0.5)*floor($angle*rand()+0.5)]" info:` ss6=`convert xc: -format "%[fx: sign(rand()-0.5)*floor($angle*rand()+0.5)]" info:` if [ "$mode" = "both" ]; then or1="rotate $rr1 skewX $ss1" or2="rotate $rr2 skewX $ss2" or3="rotate $rr3 skewX $ss3" or4="rotate $rr4 skewX $ss4" or5="rotate $rr5 skewX $ss5" or6="rotate $rr6 skewX $ss6" elif [ "$mode" = "skew" ]; then or1="skewX $ss1" or2="skewX $ss2" or3="skewX $ss3" or4="skewX $ss4" or5="skewX $ss5" or6="skewX $ss6" elif [ "$mode" = "rotate" ]; then or1="rotate $rr1" or2="rotate $rr2" or3="rotate $rr3" or4="rotate $rr4" or5="rotate $rr5" or6="rotate $rr6" fi chars="A B C D E F G H I J K L M N O P Q R S T U V W X Y Z a b c d e f g h i j k l m n o p q r s t u v w x y z 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9" charsArray=($chars) nchars=${#charsArray[*]} nchars1=`convert xc: -format "%[fx: $nchars - 1]" info:` pp1=`convert xc: -format "%[fx: floor($nchars1*rand()+0.5)]" info:` pp2=`convert xc: -format "%[fx: floor($nchars1*rand()+0.5)]" info:` pp3=`convert xc: -format "%[fx: floor($nchars1*rand()+0.5)]" info:` pp4=`convert xc: -format "%[fx: floor($nchars1*rand()+0.5)]" info:` pp5=`convert xc: -format "%[fx: floor($nchars1*rand()+0.5)]" info:` pp6=`convert xc: -format "%[fx: floor($nchars1*rand()+0.5)]" info:` cc1=${charsArray[$pp1]} cc2=${charsArray[$pp2]} cc3=${charsArray[$pp3]} cc4=${charsArray[$pp4]} cc5=${charsArray[$pp5]} cc6=${charsArray[$pp6]} fx=1.1 fy=2 bx1=`convert xc: -format "%[fx: 150 + $fx*$xx1]" info:` bx2=`convert xc: -format "%[fx: 150 + $fx*$xx2]" info:` bx3=`convert xc: -format "%[fx: 150 + $fx*$xx3]" info:` bx4=`convert xc: -format "%[fx: 150 + $fx*$xx4]" info:` bx5=`convert xc: -format "%[fx: 150 + $fx*$xx5]" info:` bx6=`convert xc: -format "%[fx: 150 + $fx*$xx6]" info:` by1=`convert xc: -format "%[fx: 40 + $fy*$yy1]" info:` by2=`convert xc: -format "%[fx: 40 + $fy*$yy2]" info:` by3=`convert xc: -format "%[fx: 40 + $fy*$yy3]" info:` by4=`convert xc: -format "%[fx: 40 + $fy*$yy4]" info:` by5=`convert xc: -format "%[fx: 40 + $fy*$yy5]" info:` by6=`convert xc: -format "%[fx: 40 + $fy*$yy6]" info:` # create image convert -size 290x70 xc:$undercolor -bordercolor $bordercolor -border 5 \ -fill black -stroke $textcolor -strokewidth 1 -font $font -pointsize $pointsize \ -draw "translate ${xx1},${yy1} $or1 gravity center text 0,0 '$cc1'" \ -draw "translate ${xx2},${yy2} $or2 gravity center text 0,0 '$cc2'" \ -draw "translate ${xx3},${yy3} $or3 gravity center text 0,0 '$cc3'" \ -draw "translate ${xx4},${yy4} $or4 gravity center text 0,0 '$cc4'" \ -draw "translate ${xx5},${yy5} $or5 gravity center text 0,0 '$cc5'" \ -draw "translate ${xx6},${yy6} $or6 gravity center text 0,0 '$cc6'" \ -fill none -strokewidth 2 \ -draw "bezier ${bx1},${by1} ${bx2},${by2} ${bx3},${by3} ${bx4},${by4}" \ -draw "polyline ${bx4},${by4} ${bx5},${by5} ${bx6},${by6}" \ $tmp0 # resize if necessary if [ "$resize" != "100" ]; then convert $tmp0 -resize ${resize}% "$outfile" else convert $tmp0 "$outfile" fi exit 0