Legacy ImageMagick Discussions Archive

Hi all,

I am looking for a developer ImageMagick/MagickWand developer to help me port an ImageMagick script to MagickWand C interface, and I am hoping someone on this board might be able to (a) help me out, or (b) give me some advice on how to find a programmer for a small task like this. (The Im script to be ported is very short).

I apologize for spamming the board, but I am at a loss of where to go for help, and how to find an Im programmer.

Please pm me if you may be able to help me out ...or respond here, either way

Cheers,
Brett

Requesting the help of a developer (for assistance or hire) is permissible on this board. Why not post your script so we can assess how easy / difficult it would be to port it to the MagickWand API.

Thanks for the reply
The script is taken from Fred ImageMagick Scripts (script doc is at: http://www.fmwconcepts.com/imagemagick/ ... /index.php), so all credit goes to Fred Weinhaus, who is aware that I am trying to port it.

I forgot to mention in the original post, that I would happily send a small paypal payment to anyone for there time invested in helping me out.
Any thoughts?

Why MagickWand? What is wrong with using the script as is?

I would like to be able to use it in another app of mine, written in Objective-C, and I already have the MagicWand interface integrated quite well for other functions.

It could be consuming to convert the script to low level MagickWand API calls, however, it would be quite simple to use the convert command MagickWand API call, ConvertImageCommand(). With it, you can simply supply the existing command line arguments from the script and your coding effort would be minimal.

Hmmm....I hadn't thought of that. I'll give it a shot.
Many thanks!

Another quick question.
Why can't I find doc on ConvertImageCommand()? Short of a few uncommented examples online, I am having trouble figuring out the syntax.

You can access all commands via the MagickCommandGenesis() interface, found in wand/mogrify.c. These are utilized from the command line wrappers in utilities/*.c. These API calls are undocumented because they are primarily used for the command line programs. However, if we get enough users that use the methods, we'll export them as officially supported API calls and document them on the ImageMagick web pages.

This is almost working. One last question: how do I extract the image? Ideally, I would like to use MagickGetImageBlob() from the magicwand, but using your suggested technique, I have no idea how. Any ideas?

Use MagickCommandGenesis() and write your image to a file and then read the image from the file into the blob. You might be able to get something going by setting the blob or file members of the ImageInfo structure although we have not tried it before. You can also read or write from file descriptors (e.g. filename fd:1).

Hello,

another vote here for the public MagickCommandGenesis(),
and probably some samples in Objective C.

Some times there is a need to do something without getting too deep into magick's API.
It may have a in impact on performance, but it may be acceptable in some scenarios for the
apps that are not image processing oriented...

Does anybody have a sample where MagickCommandGenesis() is called in Objective C ? and it is working ?

brspurri wrote:Thanks for the reply
The script is taken from Fred ImageMagick Scripts (script doc is at: http://www.fmwconcepts.com/imagemagick/ ... /index.php), so all credit goes to Fred Weinhaus, who is aware that I am trying to port it.

I forgot to mention in the original post, that I would happily send a small paypal payment to anyone for there time invested in helping me out.

Code: Select all

#!/bin/bash
#
# Developed by Fred Weinhaus 4/4/2010 .......... revised 4/4/2010
# 
# USAGE: cartoon [-m method] [-n numcolors] [-i imagefilter] [-e edgefilter] [-p pctedges] [-s smooth] infile outfile
# USAGE: cartoon [-h or -help]
# 
# OPTIONS:
# 
# -m      method            method of color reduction; choices are 1 or 2;
#                           default=1
# -n      numcolors         number of desired colors; integer>0; default=10
# -i      imagefilter       size of median filter to preprocess image; 
#                           integer>=0; default=2
# -e      edgefilter        size of median filter to preprocess grayscale image 
#                           before extracting gradient edges; integer>=0; default=2
# -p      pctedges          percentage of edges to use from gradient images; 
#                           0<=integer<=100; default=75
# -s      smooth            size of blur filter to smooth the image before 
#                           applying the edges; float>=0
# 
###
# 
# NAME: CARTOON 
# 
# PURPOSE: To create a cartoon-like appearance to an image.
# 
# DESCRIPTION: CARTOON creates a cartoon-like appearance to an image. The 
# image is color reduced to try to achieve the desired number of colors. There 
# are two methods to do this. The first is not terribly sensitive to the 
# desired number of colors. Values in the range of about 6-14 generally produce 
# the same result. But the image can be a bit noisy/grainy, so post smoothing 
# is generally needed. The second produces different results for different 
# desired number of colors and generally is not as noise sensitive. Edges can 
# then be superimposed onto the image. The edges are produced by a gradient 
# edge detector.
# 
# 
# ARGUMENTS: 
# 
# -m method ... METHOD is the color reduction method. The choices are 1 or 2. 
# Method 1 uses the IM -colors function channel-by-channel. Method 2 computes 
# a -fx formula and is applied via -clut. The default=1
# 
# -n numcolors ... NUMCOLORS is the desired number of reduced colors. Values 
# are integers>0. The default=10.
# 
# -i imagefilter ... IMAGEFILTER is the size of a median filter that will be 
# applied to the image before reducing colors. Values are integers>=0. The 
# default=2.
# 
# -e edgefilter ... EDGEFILTER is the size of a median filter that will be 
# applied to a grayscale version of the image before extracting edges. Values 
# are integers>=0. The default=2.
# 
# -p pctedges ... PCTEDGES is the percentage of the edges from the gradient 
# edge extraction from the grayscale image to overlay on the image. Values 
# are 0<=integer<=100. The default=75.
# 
# -s smooth ... SMOOTH is the amount of (-blur) smoothing to apply to the color 
# reduced image before the edges are overlayed. Values are floats>=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
method=1			# color reduction method: 1 or 2
numcolors=10		# number of colors
imagefilter=2		# median filter image
edgefilter=2		# median filter grayscale image for edges
pctedges=75			# percent edge threshold
smooth=1			# post smooth image before applying edges

# 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 14 ]
	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
					   ;;
				-m)    # get method
					   shift  # to get the next parameter
					   # test if parameter starts with minus sign 
					   errorMsg="--- INVALID METHOD SPECIFICATION ---"
					   checkMinus "$1"
					   method=`expr "$1" : '\([0-9]*\)'`
					   [ "$method" = "" ] && errMsg "--- METHOD=$method MUST BE A NON-NEGATIVE INTEGER ---"
					   [ $method -ne 1 -a $method -ne 2 ] && errMsg "--- METHOD=$method MUST BE EITHER 1 OR 2 ---"
					   ;;
				-n)    # get  numcolors
					   shift  # to get the next parameter
					   # test if parameter starts with minus sign 
					   errorMsg="--- INVALID NUMCOLORS SPECIFICATION ---"
					   checkMinus "$1"
					   numcolors=`expr "$1" : '\([0-9]*\)'`
					   [ "$numcolors" = "" ] && errMsg "--- NUMCOLORS=$numcolors MUST BE A NON-NEGATIVE INTEGER VALUE (with no sign) ---"
					   test=`echo "$numcolors < 0" | bc`
					   [ $test -eq 1 ] && errMsg "--- NUMCOLORS=$numcolors MUST BE A POSITIVE INTEGER ---"
					   ;;
				-i)    # get  imagefilter
					   shift  # to get the next parameter
					   # test if parameter starts with minus sign 
					   errorMsg="--- INVALID IMAGEFILTER SPECIFICATION ---"
					   checkMinus "$1"
					   imagefilter=`expr "$1" : '\([0-9]*\)'`
					   [ "$imagefilter" = "" ] && errMsg "--- IMAGEFILTER=$imagefilter MUST BE A NON-NEGATIVE INTEGER VALUE (with no sign) ---"
					   ;;
				-e)    # get  edgefilter
					   shift  # to get the next parameter
					   # test if parameter starts with minus sign 
					   errorMsg="--- INVALID EDGEFILTER SPECIFICATION ---"
					   checkMinus "$1"
					   edgefilter=`expr "$1" : '\([0-9]*\)'`
					   [ "$edgefilter" = "" ] && errMsg "--- EDGEFILTER=$edgefilter MUST BE A NON-NEGATIVE INTEGER VALUE (with no sign) ---"
					   ;;
				-p)    # get pctedges
					   shift  # to get the next parameter
					   # test if parameter starts with minus sign 
					   errorMsg="--- INVALID PCTEDGES SPECIFICATION ---"
					   checkMinus "$1"
					   pctedges=`expr "$1" : '\([0-9]*\)'`
					   [ "$pctedges" = "" ] && errMsg "--- PCTEDGES=$pctedges MUST BE A NON-NEGATIVE INTEGER VALUE (with no sign) ---"
					   test1=`echo "$pctedges < 0" | bc`
					   test2=`echo "$pctedges > 100" | bc`
					   [ $test1 -eq 1 -o $test2 -eq 1 ] && errMsg "--- PCTEDGES=$pctedges MUST BE AN INTEGER BETWEEN 0 AND 100 ---"
					   ;;
				-s)    # get  smooth
					   shift  # to get the next parameter
					   # test if parameter starts with minus sign 
					   errorMsg="--- INVALID SMOOTH SPECIFICATION ---"
					   checkMinus "$1"
					   smooth=`expr "$1" : '\([.0-9]*\)'`
					   [ "$smooth" = "" ] && errMsg "--- SMOOTH=$smooth MUST BE A NON-NEGATIVE FLOAT (with no sign) ---"
					   ;;
				 -)    # 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
tmpA1="$dir/cartoon_1_$$.mpc"
tmpB1="$dir/cartoon_1_$$.cache"
tmpA2="$dir/cartoon_2_$$.mpc"
tmpB2="$dir/cartoon_2_$$.cache"
tmpA3="$dir/cartoon_3_$$.mpc"
tmpB3="$dir/cartoon_3_$$.cache"
trap "rm -f $tmpA1 $tmpB1 $tmpA2 $tmpB2 $tmpA3 $tmpB3; exit 0" 0
trap "rm -f $tmpA1 $tmpB1 $tmpA2 $tmpB2 $tmpA3 $tmpB3; exit 1" 1 2 3 15

# read the input image and filter image into the temp files and test validity.
convert -quiet -regard-warnings "$infile" -colorspace RGB +repage "$tmpA1" ||
	errMsg "--- FILE $infile DOES NOT EXIST OR IS NOT AN ORDINARY FILE, NOT READABLE OR HAS ZERO SIZE  ---"


# define x and y derivative filters
# DX
# -1 0 1
# -1 0 1
# -1 0 1
dx="-1,0,1,-1,0,1,-1,0,1"
# DY
# 1 1 1
# 0 0 0
# -1 -1 -1
dy="1,1,1,0,0,0,-1,-1,-1"


# set up color image median
if [ $imagefilter -ne 0 ]; then
	medianize1="-median $imagefilter"
else
	medianize1=""
fi

# set up grayscale image median
if [ $edgefilter -ne 0 ]; then
	medianize2="-median $edgefilter"
else
	medianize2=""
fi

# set up smoothing
if [ "$smooth" != "0" ]; then
	smoothing="-blur 0x$smooth"
else
	smoothing=""
fi

# reduce colors
if [ $method -eq 1 ]; then
	convert $tmpA1 $medianize1 -separate -colors $numcolors +dither \
		-combine $smoothing $tmpA2
else
	convert \( $tmpA1 -median 2 \) \
		\( -size 1x256 gradient: -rotate 90 \
		-fx "floor(u*$numcolors+0.5)/$numcolors" \) \
		-clut $tmpA2
fi

# create and composite image with edges
if [ $pctedges -ne 0 ]; then
	# create thresholded gradient edge image
	convert \( $tmpA1 -colorspace gray $medianize2 \) \
		\( -clone 0 -bias 50% -convolve "$dx" -solarize 50% \) \
		\( -clone 0 -bias 50% -convolve "$dy" -solarize 50% \) \
		\( -clone 1 -clone 1 -compose multiply -composite -gamma 2 \) \
		\( -clone 2 -clone 2 -compose multiply -composite -gamma 2 \) \
		-delete 0-2 -compose plus -composite -threshold ${pctedges}% $tmpA3

	# composite with reduced color image
	convert $tmpA2 $tmpA3 -compose multiply -composite $outfile
else
	convert $tmpA2 $outfile
fi
exit 0

Any thoughts?

Unfortunately, I do not do API scripting. But as this is my script, please remind me of your application and usage of my script. You may do so offline if you want to my direct email fmw at alink dot net.