static PyObject *
image_set_offset(PyObject *self, PyObject *args)
{
    int x, y;
    PyObject *pyim;

    if(!PyArg_ParseTuple(args,"Oii",&pyim,&x,&y))
    { 
	return NULL;
    }

    IImage *i = (IImage *)PyCObject_AsVoidPtr(pyim);
    if(NULL == i)
    {
	return NULL;
    }

    bool ok = i->set_offset(x,y);
    if(!ok)
    {
	PyErr_SetString(PyExc_ValueError, "Offset out of bounds");
	return NULL;
    }

    Py_INCREF(Py_None);
    return Py_None;
}