使用Magick ++和openMPI编译C ++代码

Question

I'm trying to compile my C++ code using Magick++ library to manipulate images in a distributed way using openMPI and I get some errors when I try to compile it.

This is my code:

#include "mpi.h"
#include <stdio.h>
#include <iostream>
#include <Magick++.h>
using namespace std; 
using namespace Magick; 

int main(int argc, char **argv){

int rank, numtask;

InitializeMagick(*argv);

Image image;
try { 
    // Read a file into image object 
    image.read( "test_image.jpg" );
    image.type( GrayscaleType );
    Blob blob; 
    image.magick( "JPEG" ); // Set JPEG output format 
    image.write( &blob );

} 
catch( Exception &error_ ){ 
    cout << "Caught exception: " << error_.what() << endl; 
    return 1; 
 } 

//Now in the "distributed enviroment" I just print an hello world to test it. 
MPI_Init(&argc,&argv);

MPI_Comm_rank(MPI_COMM_WORLD, &rank);
MPI_Comm_size(MPI_COMM_WORLD, &numtask);

cout<<"HelloWorld\n";

MPI_Finalize();

}

this is the command that I type on the shell

mpiCC openmpi_project.cc -o openmpi_project

and this is the output of the shell

openmpi_project.cc:(.text+0x1d): undefined reference to "Magick::InitializeMagick(char const*)"

openmpi_project.cc:(.text+0x29): undefined reference to "Magick::Image::Image()"

openmpi_project.cc:(.text+0x5d): undefined reference to "Magick::Image::read(std::string const&)"

openmpi_project.cc:(.text+0x86): undefined reference to "Magick::Image::type(MagickCore::ImageType)"

openmpi_project.cc:(.text+0x92): rundefined reference to "Magick::Blob::Blob()"

openmpi_project.cc:(.text+0xc6): undefined reference to "Magick::Image::magick(std::string const&)"

openmpi_project.cc:(.text+0xf1): undefined reference to "Magick::Image::write(Magick::Blob*)"

openmpi_project.cc:(.text+0xfd): undefined reference to "Magick::Blob::~Blob()"

openmpi_project.cc:(.text+0x158): undefined reference to "Magick::Image::~Image()"

openmpi_project.cc:(.text+0x1d3): undefined reference to "Magick::Blob::~Blob()"

openmpi_project.cc:(.text+0x261): undefined reference to "Magick::Image::~Image()"

/tmp/ccqFzUdy.o:(.gcc_except_table+0x58): undefined reference to "typeinfo for Magick::Exception"

Answer 1

ImageMagick ships with config utilities. For Magick++ this utility is Magick++-config . See the Usage sub-section under the API docs .

LDFLAGS=$(Magick++-config --ldflags)
CXXFLAGS=$(Magick++-config --cxxflags)
$(CC) $CXXFLAGS openmpi_project.cc $LDFLAGS -o openmpi_project

Jump over to the MPI compiling/linking docs , and integrate Magick++'s additional flags to mpiCC

LDFLAGS=$(Magick++-config --ldflags)
CXXFLAGS=$(Magick++-config --cxxflags)
mpiCC --with-wrapper-cxxflags=$CXXFLAGS openmpi_project.cc \
      --with-wrapper-ldflags=$LDFLAGS -o openmpi_project