[Insight-users] Re: Passing ITK images in/out of C-like functions

[Luis Ibanez]

Hi Vijay,

In your code, the variable "kimag" is a raw pointer
to a SmartPointer of an ITK image.  If you want to
address methods from the image type you have to
unreference the pointer by using the notation (*kimage).


Like in :


             (*kimage)->GetSpacing();


Please let us know if you have further questions,


    Thanks


      Luis


------------------------
Vijay Prashanth wrote:

> Hi Luis,
>               Thank you very much for the solution regarding the usage of
> smart pointers. It was helpful in solving the problem. Actually I had also
> arrived at it but I used the          SetReferenceCount and GetReferenceCount
> methods for increasing the reference count instead the Register method You
> had suggested.
>  
>              But I would like to clarify a point on the OptionA.
>  
>               In the solution -Option A:
>  
>               // before calling the function
>                typedef itk::Image<unsigned char, 2>  ImageType;
>                Image Type::Pointer img;
>                void * pimg = &img;
>                myFunctionForCreatingAnImage( pimg, k1, k2, k3,... kn );
> 
>               // inside the function
>               void  myFunctionForCreatingAnImage( void * pimg, k1, k2 ... )
>              {
>                 typedef itk::Image<unsigned char, 2>  ImageType;
>  
>                 // your code for the importer filter..
> 
>                 ImageType::Pointer *kimg = (ImageType::Pointer *)pimg;
>                 *kimg = importer->GetOutput();
>                 return;
>             }
> 
>              Now if we use 'kimg' to call some of the methods of itk::Image
> class inside the function 'myFunctionForCreatingAnImage( )
>              an error occured like" the function does not belong to 'kimg'. I
> think this because it is a pointer of type smart pointer class and so it does
> not know the itk::image methods.
>              Do we have to use like (*kimg)->itk::imagemethods( ) , in order
> to obtain the address of the itk::image object stored in the smart pointer?.
> 
>            Option B was working good(increasing the reference count).
> 
>