Topflappen häkeln mit Unix
Wie kriegt man sein Lieblingslogo in die Küche? Als Topflappen natürlich, und die Vorlage macht man natürlich mit Unix:
So'n Lappen hat normalerweise ungefähr 50×50 Felder, also rechnet man sich das Bild erst auf 50 Pixel klein, und dann wieder groß mit etwas Rand. Dabei reduziert man noch die Anzahl der Farben
convert oobd_logo_simple_colors.png -resize 50 -filter point -flatten -alpha off -resize 500 -blur 0 -gravity center -extent 600x600 -colors 4 oobd_new.png
bzw. man dreht es um 45°
convert oobd_logo_simple_colors.png -rotate "45" -resize 50 -filter point -flatten -alpha off -resize 500 -blur 0 -gravity center -extent 600x600 -colors 4 oobd_new.png
Dann bedient man sich noch des großartigen Scripts von Fred Weinhaus, um ein Rasternetz zum besseren Abzählen darüber zu bekommen, und fertig. Jetzt muß die Vorlage nur noch zu Grossmuttern in die Produktion 
- grid.sh
#!/bin/bash # # Developed by Fred Weinhaus 10/22/2007 .......... revised 1/1/2008 # # USAGE: grid [-s spacing] [-c color] [-t thickness] [-o opacity] infile outfile # USAGE: grid [-h or -help] # # OPTIONS: # # -s spacing x,y spacing between grid lines; default=16,16 or 16; # second number is defaulted to the first # -c color color of grid lines; default="black" # -t thickness thickness of grid lines; default=1 # -o opacity opacity of grid lines opacity between 0.0 and 1.0; # opacity=0 is transparent; opacity=1 is opaque; # default=1 # ### # # NAME: GRID # # PURPOSE: To superimpose a set of horizontal and/or vertical grid lines # on an image. # # DESCRIPTION: GRID superimposes a set of horizontal and/or vertical grid # lines on an image. Parameters are available to select the grid line color, # thickness and opacity. # # # OPTIONS: # # -s spacing ... SPACING specifies the horizontal (x) and vertical (y) grid # offset between lines. Spacing must be provided as integer values. If the # second value is left off, then it will be set identical to the first. If # only vertical lines are desired, set the horizontal (x) spacing larger # than the width of the image. If only horizontal lines are desired, set # the vertical (y) spacing larger than the height of the image. The default=8. # Note: if you want the bottom and/or right grid line to show, then the image # dimension(s) must be a multiple of the grid spacing plus 1. # # -c color ... COLOR is the color of the grid lines. Any valid IM color # specification is allowed. Be sure to color values in double quotes. # The default="black". # # -t thickness ... THICKNESS is the grid line thickness. Values are positive # integers. The default=1 # # -o opacity ... OPACITY is the grid line opacity. Values are non-negative # floats between 0.0 and 1.0. The default=1 # # 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 spacing=16 color="black" thickness=1 opacity=1 # 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:" "$@" sed >&2 -n '/^###/q; /^#/!q; s/^#//; s/^ //; 4,$p' "$PROGDIR/$PROGNAME" } usage2() { echo >&2 "" echo >&2 "$PROGNAME:" "$@" sed >&2 -n '/^######/q; /^#/!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 10 ] 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 ;; -s) # get spacing shift # to get the next parameter - spacing # test if parameter starts with minus sign errorMsg="--- INVALID SPACING SPECIFICATION ---" checkMinus "$1" spacing="$1," ;; -c) # get color shift # to get the next parameter - lineval # test if parameter starts with minus sign errorMsg="--- INVALID COLOR SPECIFICATION ---" checkMinus "$1" # test lineval values color="$1" ;; -t) # get thickness shift # to get the next parameter - thickness # test if parameter starts with minus sign errorMsg="--- INVALID THICKNESS SPECIFICATION ---" checkMinus "$1" # test width values thickness=`expr "$1" : '\([0-9]*\)'` [ "$thickness" = "" -o $thickness -eq 0 ] && errMsg "--- THICKNESS=$thickness MUST BE A POSITIVE INTEGER ---" ;; -o) # get opacity shift # to get the next parameter - opacity # test if parameter starts with minus sign errorMsg="--- INVALID OPACITY SPECIFICATION ---" checkMinus "$1" # test width values opacity=`expr "$1" : '\([.0-9]*\)'` [ "$opacity" = "" ] && errMsg "OPACITY=$opacity IS NOT A NON-NEGATIVE FLOATING POINT NUMBER" opacitytest=`echo "$opacity > 1" | bc` [ $opacitytest -eq 1 ] && errMsg "OPACITY=$opacity MUST BE BETWEEN 0.0 AND 1.0" ;; -) # 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 [ "$outfile" = "" ] && errMsg "NO OUTPUT FILE SPECIFIED" # setup temporary images and auto delete upon exit # use mpc/cache to hold input image temporarily in memory tmpA="$dir/profile_$$.mpc" tmpB="$dir/profile_$$.cache" trap "rm -f $tmpA $tmpB; exit 0" 0 trap "rm -f $tmpA $tmpB; exit 1" 1 2 3 15 # if convert -quiet -regard-warnings "$infile" +repage "$tmpA" then : 'do nothing - continue processing below' else errMsg "--- FILE $infile DOES NOT EXIST OR IS NOT AN ORDINARY FILE, NOT READABLE OR HAS ZERO SIZE ---" fi # get image dimensions width=`identify -format %w $tmpA` height=`identify -format %h $tmpA` width1=`expr $width - 1` height1=`expr $height - 1` xinc=`echo "$spacing" | cut -d, -f1` yinc=`echo "$spacing" | cut -d, -f2` [ "$yinc" = "" ] && yinc=$xinc testx=`expr $xinc : '[0-9]*'` testy=`expr $yinc : '[0-9]*'` [ $testx -eq 0 -o $testy -eq 0 ] && errMsg "--- SPACING MUST BE AN INTEGER ---" # get string for drawing grid lines drawstr="" if [ $yinc -le $height ] then i=0 while [ $i -le $height ] do drawstr="$drawstr M 0,$i L $width1,$i" i=`expr $i + $yinc` done fi if [ $xinc -le $width ] then i=0 while [ $i -le $width ] do drawstr="$drawstr M $i,0 L $i,$height1" i=`expr $i + $xinc` done fi # process image convert $tmpA -fill none -stroke $color -strokewidth $thickness -draw "stroke-opacity $opacity path '$drawstr'" $outfile exit 0