Need help accessing AVT camera (with wrapper?)!

**emigrand** · 4th April 2012, 11:07

Hello, I urgently need your help!

I'm trying to involve an AVT Pike camera into my Qt project. When I add the libraries to my .pro-file and instantiate a CFGCamera object (gives access to camera functionalities), the programm fails link(?) and gives me following errors:

:: error: undefined reference to '_imp__ZN9CFGCameraD1Ev'
:: error: undefined reference to '_imp__ZN9CFGCameraD1Ev'
:: error: undefined reference to '_imp__ZN9CFGCameraD1Ev'
:: error: collect2: ld returned 1 exit status

Since I use the MinGW compiler, I think that the following thread in AVT's Knowledge Base is the solution to my problems:

FireGrab with Dev C++ and MinGW/GCC compiler

The CFGCamera object of the MS VS C++ library FGCamera.lib could not be converted to MinGW compatible *.a library. That's why there's the C-wrapper FGWrap.dll providing the functions of the FireGrab interface to a camera handle instead of an CFGCamera object.

The FireGrab\Lib\Extra\FGWrap.lib could be loaded to your Dev C++ project easily as shown at the modified WrapSample.
FGCamera.lib has to be included just to initialize the module and get the nodelist.

But even with this approach I cannot access the camera. Can somebody tell me what I am doing wrong? My .pro-file now looks like this:

Qt Code:

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INCLUDEPATH += C:/FirePackage/FireGrab/Lib/Extra
LIBS += C:/FirePackage/FireGrab/Lib/Extra/FGWrap.lib
LIBS += C:/FirePackage/FireGrab/Lib/FGCamera.lib

INCLUDEPATH += C:/FirePackage/FireGrab/Lib/Extra
LIBS += C:/FirePackage/FireGrab/Lib/Extra/FGWrap.lib
LIBS += C:/FirePackage/FireGrab/Lib/FGCamera.lib

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The Lib folder contains following files:

FGCamara.dll
convert.c
basetype.h
convert.h
errstat.h
FGCamera.h
FGCamera.lib
FGCamera_omf.lib

The Extra folder contains following files:

FGWrap.dll
Camera.h
FGWrap.h
IsoDma.h
FGWrap.cpp
FGWrap.lib
FGWrap_omf.lib

My main.cpp:

Qt Code:

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#include <fgcamera.h>
#include <fgwrap.h>
 
int main(int argc, char *arbv[])
{
   QApplication a(argc, argv);
   FGHandle hCamera; //this is the substitute for the CFGCamera object
   FGNODEINFO NodeInfo[3];
   UINT32 NodeCnt;
 
   FGInitModule(NULL);
   FGGetNodeList(NodeInfo,3,&NodeCnt);
 
   hCamera = NULL;
   FGGetCameraHandle(&hCamera,&NodeInfo[0].Guid,NULL); //here it exits
   ...
   return a.exec();
}

#include <fgcamera.h>
#include <fgwrap.h>

int main(int argc, char *arbv[])
{
   QApplication a(argc, argv);
   FGHandle hCamera; //this is the substitute for the CFGCamera object
   FGNODEINFO NodeInfo[3];
   UINT32 NodeCnt;
   
   FGInitModule(NULL);
   FGGetNodeList(NodeInfo,3,&NodeCnt);
   
   hCamera = NULL;
   FGGetCameraHandle(&hCamera,&NodeInfo[0].Guid,NULL); //here it exits
   ...
   return a.exec();
}

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When I execute it, it exits at the mentioned line with a return value -1073741515. Since this is adapted from a sample I am pretty sure that the parameters etc. are fine. I could access the camera with MSVS2010 Express as well, no problem.

So how do I use the wrapper? Maybe someone could test it on his system, the library can be downloaded here.
Another possibility might be to generate a MinGW compatible library from FGCamera.dll with pexports(!?), but I don't know how to do that and if it's feasible, because AVT says it is not (see above).

Last to mention my setup:
Qt 4.7.0
Qt Creator 2.0.1
MinGW-Compiler
Windows 7

Sorry for cross-posting(?), but initially I picked up an old thread in the Qt-programming forum. I didn't want to bother them with newbie questions anymore.

Thanks for your assistance.