extern int		uc_height, uc_width;
extern long		uc_ldif;
extern uchar	*uc_uend, *uc_c, *uc_m, *uc_y;
extern void		undo_copy_cmy(void);
extern void		undo_swap_cmy(void);
extern void		undo_copy_m(void);
extern void		undo_swap_m(void);
