out of memory exception

[AFTER DISCUSSION in comments to the answer]

If you did not pay attention on System.IDisposal, with System.Drawing you could possibly leak a lot of memory!

This interface allows to call its method called System.IDisposable.Dispose() usually used to clean different things. Very typically it is used by System.Drawing to dispose unmanages resources.

Here is how you should do:

//sloppy version:
try {
   Brush myBrush = new SolidBrush(/*...*/);
   //use myBrush;
} finally { //in case exception was thrown
   myBrush.Dispose();
}

//This is strictly equivalent to the following code
//using special construct "using" designed for automatic call to Dispose;
//more elegant and supportable:
using (Brush myBrush = new SolidBrush(/*...*/) {
   //use myBrush
} //end using auto-calls myBrush.Dispose()

This is not just Brush. Check up every single .NET library object you create if their types implement IDisposable. When this is the case, you should always use the codelet with "using" I've demonstrated above to avoid serious leak. I don't understand how you failed to come across this important aspect before. (Maybe you're a beginner, so it's a very important thing to take into account.)

This construct and interface are one of the most important features if .NET. If you don't know it and trying to do GDI-based development, chances are, you lead a lot of unmanaged resources.

—SA