Removing GDI+ objects

[cgw122]

I am attempting to write a program to randomly select images out of a directory and set them as a desktop background. I know windows has a tool to do this, but I thought it would be interesting to it myself.

I was able to set the background without trouble, but when I set it to loop the memory usage climbs every time an image is loaded and set. Using the task manager I was able to determine that the number of GDI Objects is not increasing though. Below is the function I use to import and resize the images.

void resizeandsave()
{
   Image npic;
   string imgstring;
   std::wstring imgwstring;
   const wchar_t* imgchar;
   int i=0;
   d=opendir(".");
   if (d)
   {
	while ((dir=readdir(d)) != NULL)
	{
		i++;
		dirlist.push_back(dir->d_name);
	}
   	closedir(d);
   }
   int r=genrand_int32()%(i-1);

   imgstring=r;
   imgwstring = std::wstring(img.begin(),img.end())
   imgchar = imgwstring.c_str();
   
   Image pic(imgchar);
   npic = pic.GetThumbnailImage(1680,1050,NULL,NULL);
   npic.Save(L"wallpaper.jpg");
}

I had hoped to just put a couple of deletes at the end of the function of the form
delete pic;
this however gives me the compile error "cannot convert from Gdiplus::Image to void *"

Any suggestions of how to deal with the memory, or to close the Image objects?

[Factors]

... The delete keyword can only be used to delete dynamically allocated memory. And to answer your question. ZeroMemory :D. Or something like that.

[cire]

Does that even compile?

According to http://msdn.microsoft.com/en-us/library/windows/desktop/ms535394%28v=vs.85%29.aspx GetThumbnailImage returns a pointer (which you own, and therefore must delete.)

Scaling the image would be a better thing to do than creating a large thumbnail image.
http://msdn.microsoft.com/en-us/library/windows/desktop/ms533836%28v=vs.85%29.aspx