Assistance with using ImageMagick with MinGW

[168gr]

Very brief personal background -

I am by no means an experienced or accomplished programmer. I did complete a CS minor as an undergrad (finished ~15 years ago), but went into a non-computer related field. Periodically I've written programs for simple tasks or my own entertainment. These days I would say I'm on the edge of functional literacy with C and unix. I last used ImageMagick on Linux in 2001 or 2002. It's a little different now. Apologies if some of these questions are annoyingly basic ... I think I just need some memory jogging.


Presently I'm working on a simple win32 program that needs to do some very basic image processing and display. The MagickWand API looks great. I'm working on a Windows 7 laptop with the MinGW 1.1 compiler.

From searching this forum, it appears that the binary distributions are incompatible with MinGW. I've downloaded ImageMagick-6.8.1-9, unpacked it, all the source is there. From what I can discern from the included docs, the expectation is that people are using Visual Studio (or maybe Borland).


Can someone point me in the right direction for getting ImageMagick built on Windows with MinGW? I don't see a makefile for mingw32-make, and I don't know what (if anything) I need to do with the configure scripts. Additional libraries I need to acquire? Anything special to link the ImageMagick stuff to my as-yet trivially simple 'hello world' win32 program?

I think if I can get a simple win32 program that includes this basic MagickWand routine to compile and run, I can take it from there.

Thank you.

[168gr]

Problem #1 solved. Shook a little rust of my brain, and using a msys shell, I could run ./configure and then make. MinGW built ImageMagick without complaint.

Problem #2 is probably equally trivial ... I realize this isn't really an ImageMagick-specific issue but a makefile/linking issue.

Here's the error:

Code: Select all

gcc -o "testprogram.exe" obj/winmain.o obj/callbacks.o obj/resource.o -s -lcomctl32 -Wl,--subsystem,windows
obj/callbacks.o:callbacks.c:(.text+0x55): undefined reference to `MagickWandGenesis'
obj/callbacks.o:callbacks.c:(.text+0x5a): undefined reference to `NewMagickWand'
obj/callbacks.o:callbacks.c:(.text+0x6c): undefined reference to `MagickReadImage'
obj/callbacks.o:callbacks.c:(.text+0x7c): undefined reference to `MagickWriteImage'
obj/callbacks.o:callbacks.c:(.text+0x88): undefined reference to `DestroyMagickWand'
obj/callbacks.o:callbacks.c:(.text+0x91): undefined reference to `MagickWandTerminus'
collect2: ld returned 1 exit status
mingw32-make: *** [testprogram.exe] Error 1

What linking option do I need to put in there to get this to build?

Here's the makefile. (Test program is a simple do-nothing win32 prorgam from this tutorial; it's their example makefile.) I plopped the 'magick' and 'wand' directories in the 'include' directory so the compiler could find them. Not sure if this is the correct/favored way to do it, but it allowed the thing to compile without issue. Linking is the problem.

Code: Select all

HEADERS = include/callbacks.h include/resource.h
OBJS =	obj/winmain.o obj/callbacks.o obj/resource.o
INCLUDE_DIRS = -I.\include

WARNS = -Wall

CC = gcc
CFLAGS = -O3 -std=c99 -D UNICODE -D _UNICODE -D _WIN32_IE=0x0500 -D WINVER=0x500 ${WARNS}
LDFLAGS = -s -lcomctl32 -Wl,--subsystem,windows
RC = windres

all : testprogram.exe

testprogram.exe : ${OBJS}
	${CC} -o "$@" ${OBJS} ${LDFLAGS}

clean :
	del obj\*.o "testprogram.exe"

obj/%.o : src/%.c ${HEADERS}
	${CC} ${CFLAGS} ${INCLUDE_DIRS} -c $< -o $@

obj/resource.o : res/resource.rc res/Application.manifest res/Application.ico include/resource.h
	${RC} -I.\include -I.\res -i $< -o $@

Thank you.

[magick]

Type

• MagickWand-config --cflags --cppflags

to display the expected compile flags to build custom code for MagickWand. Type

• MagickWand-config --ldflags --libs

to display the loader flags.

[168gr]

Thank you -

For some reason pkg-config isn't part of the MinGW install.

Code: Select all

$ ./MagickWand-config --cflags --cppflags
./MagickWand-config: line 41: pkg-config: command not found
./MagickWand-config: line 47: pkg-config: command not found

$ ./MagickWand-config --ldflags --libs
./MagickWand-config: line 50: pkg-config: command not found
./MagickWand-config: line 53: pkg-config: command not found

After getting the GTK+ runtime from http://sourceforge.net/projects/gimp-win/files/ and pkg-config.exe from http://www.gtk.org/download/win32.php ...

Code: Select all

$ ./MagickWand-config --cflags
Package MagickWand was not found in the pkg-config search path.
Perhaps you should add the directory containing `MagickWand.pc'
to the PKG_CONFIG_PATH environment variable
No package 'MagickWand' found

$ echo $PKG_CONFIG_PATH
~/project/ImageMagick-6.8.1-9/wand

Not sure why it was complaining. So after screwing around with pkg-config.exe for a while, I re-ran the ImageMagick configure script, and at the end it printed this helpful bit

Code: Select all

Options used to compile and link:
  PREFIX          = /usr/local
  EXEC-PREFIX     = /usr/local
  VERSION         = 6.8.1
  CC              = gcc -std=gnu99 -std=gnu99
  CFLAGS          = -fopenmp -g -O2 -Wall -DMAGICKCORE_HDRI_ENABLE=0 -DMAGICKCORE_QUANTUM_DEPTH=16
  CPPFLAGS        = -I/usr/local/include/ImageMagick -D_DLL -D_MT
  PCFLAGS         = -fopenmp -DMAGICKCORE_HDRI_ENABLE=0 -DMAGICKCORE_QUANTUM_DEPTH=16 -D_DLL -D_MT
  DEFS            = -DHAVE_CONFIG_H
  LDFLAGS         =
  MAGICK_LDFLAGS  = -L/usr/local/lib
  LIBS            = -lMagickCore -lgdi32 -lm -lgomp -lpthread
  CXX             = g++
  CXXFLAGS        = -g -O2
  FEATURES        = OpenMP
  DELEGATES       = ps

Great, so now the Makefile reads

Code: Select all

HEADERS = include/callbacks.h include/resource.h
OBJS =	obj/winmain.o obj/callbacks.o obj/resource.o
INCLUDE_DIRS = -I.\include

WARNS = -Wall

CC = gcc
CFLAGS = -O3 -std=c99 -D UNICODE -D _UNICODE -D _WIN32_IE=0x0500 -D WINVER=0x500 ${WARNS} -fopenmp -g -O2 -Wall -DMAGICKCORE_HDRI_ENABLE=0 -DMAGICKCORE_QUANTUM_DEPTH=16
LDFLAGS = -s -lcomctl32 -Wl,--subsystem,windows
RC = windres

LIBS = -lMagickCore -lgdi32 -lm -lgomp -lpthread

all : testprogram.exe

testprogram.exe : ${OBJS}
	${CC} -o "$@" ${OBJS} ${LDFLAGS} ${LIBS}

clean :
	del obj\*.o "testprogram.exe"

obj/%.o : src/%.c ${HEADERS}
	${CC} ${CFLAGS} ${INCLUDE_DIRS} -c $< -o $@

obj/resource.o : res/resource.rc res/Application.manifest res/Application.ico include/resource.h
	${RC} -I.\include -I.\res -i $< -o $@

And an attempted make got me this error

Code: Select all

$ make
gcc -o "testprogram.exe" obj/winmain.o obj/callbacks.o obj/resource.o -s -lcomctl32 -Wl,--subsystem,windows -lMagickCore -lgdi32 -lm -lgomp -lpthread
c:/mingw/bin/../lib/gcc/mingw32/4.6.2/../../../../mingw32/bin/ld.exe: cannot find -lMagickCore
collect2: ld returned 1 exit status
make: *** [testprogram.exe] Error 1

What next? How do I tell the compiler where to find lMagickCore? Where should it be?

Thanks.

[magick]

Try -lMagickCore-Q16.

[168gr]

Try -lMagickCore-Q16.

No luck, same error.

[magick]

If you compiled ImageMagick and installed it, all libraries should by default be in /usr/local/lib. Take a look. Is there a libMagickCore-Q16.a? If so, -L/usr/local/lib -lMagickCore-Q16 should work.

[168gr]

Made a little progress ...

Changed the line in the Makefile to

Code: Select all

LIBS = -lMagickCore-Q16 -lMagickWand-Q16 -lgdi32 -lm -lgomp -lpthread

and manually copied two files:
- libMagickCore-Q16.a
- libMagickWand-Q16.a
to the c:\mingw\lib directory.

Now the compiler gets verbosely angry

Code: Select all

c:/mingw/bin/../lib/gcc/mingw32/4.6.2/../../../libMagickWand-Q16.a(wand_libMagickWand_Q16_la-magick-wand.o): In function `ClearMagickWand':
C:\MinGW\msys\1.0\home\pgg\project\ImageMagick-6.8.1-9/wand/magick-wand.c:92: undefined reference to `LogMagickEvent'
C:\MinGW\msys\1.0\home\pgg\project\ImageMagick-6.8.1-9/wand/magick-wand.c:93: undefined reference to `DestroyQuantizeInfo'
C:\MinGW\msys\1.0\home\pgg\project\ImageMagick-6.8.1-9/wand/magick-wand.c:94: undefined reference to `DestroyImageInfo'
C:\MinGW\msys\1.0\home\pgg\project\ImageMagick-6.8.1-9/wand/magick-wand.c:95: undefined reference to `DestroyImageList'

[...]
hundreds of lines of this
[...]

collect2: ld returned 1 exit status
make: *** [testprogram.exe] Error 1

[magick]

Try -lMagickWand-Q16 -lMagickCore-Q16.

[168gr]

If you compiled ImageMagick and installed it, all libraries should by default be in /usr/local/lib. Take a look. Is there a libMagickCore-Q16.a? If so, -L/usr/local/lib -lMagickCore-Q16 should work.

Success ...

Adding -L/usr/local/lib is what did it.

Thanks again for your help. I appreciate your work.

[broucaries]

the usual way to compile to mingw is croscs compile from cygwin see google

[168gr]

the usual way to compile to mingw is croscs compile from cygwin see google

Thank you, I'll give that a try.

[168gr]

the usual way to compile to mingw is croscs compile from cygwin see google

Thanks. I abandoned mingw, installed cygwin, and plopped in the binary distro of ImageMagick for cygwin. It just works. Little 'hello world' win32 program was able to call the ImageMagick routines, so I'm off to do something useful now.

I'm sure I'll be back at some point with ImageMagick specific questions now that I've bludgeoned through the environment, compiler, and linker problems.

[harry.whitehouse]

This thread was very helpful to me but some things have changed with time...

Here's the link statement that works with version 7:

gcc -Wall -fPIC -o "wand" "wand.c" -I /usr/include/ImageMagick/ -L /usr/local/lib -lMagickCore-7.Q16HDRI -lMagickWand-7.Q16HDRI