I realized I'm creating and destroying a PackedImageDesc once per scanline. Rather than a simple wrapper around some image pointers this class allocates an implementation class. This got me thinking about extra memory overhead per scanline.

Ideally I'd process in batches but I have this down inside an OpenMP loop which makes it easy.

Should I be concerned about this? Would a lighter-weight version be out of order? I can't imagine the implementation details of such a wrapper being too volatile.